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Did Russia Accidentally Provide the Best Evidence of the Syrian Government’s Involvement in Sarin Attacks?

November 13, 2017

By Bellingcat Investigation Team

Russia’s latest attempts to challenge accusations of Syrian government responsibility for the April 4th 2017 Sarin attack on Khan Sheikhoun may have inadvertently produced the best evidence yet that the Syrian government is responsible for not only the Khan Sheikhoun attack, but the earlier March 30th 2017 Sarin attack on Al-Lataminah.

During a lengthy press conference on November 2nd 2017, the Russian Foreign Ministry, Ministry of Defence and the Ministry for Industry and Trade presented its response to the Organisation for the Prohibition of Chemical Weapons – UN Joint Mission (OPCW-UN JIM) report on the Khan Sheikhoun Sarin attack. The presentation included a series of slides, which included diagrams of two types of chemical bombs, designated the MYM6000 and M4000. The slides from the presentation, with a clearer version of the bomb diagrams, were published online:

Remarkably, the Russian presentation appears to be the first-time images of these munitions have been made public, and before the press conference, no other references to MYM6000 or M4000 bombs appear online. Gregory Koblentz, Associate Professor and Director of Biodefense Graduate Program in the Schar School of Policy and Government at George Mason University, noted that “these designations match bombs declared by Syria to the OPCW”, although there appears to be no open source material that provides specifics about the types of bombs declared to the OPCW. In the press conference the source of the diagrams are described as being provided “by certain organisations”, but no more specifics are given.

In the recent report by the OPCW Fact Finding Mission (FFM) on the March 30th Al-Lataminah attack photographs of a number of items recovered from the attack site by the Syrian Civil Defence and provided to the OPCW were featured. This includes two metal filling caps that are identical in design to a filling cap recovered from the site of the April 4th attack in Khan Sheikhoun:

Left – A cap from Al-Lataminah; Right – The cap from Khan Sheikhoun

Chemical analysis of the debris and samples recovered from the March 30th attack site are consistent with the same type of Sarin being used in both incidents, Sarin which the OPCW-UN JIM report on the Khan Sheikhoun attack states is linked to the production process used by the Syrian government. While the OPCW provides evidence that links the Sarin used in both attack (as well as previous attacks) to the Syrian government, it is the Russian government, who in their attempt to defend the Syrian government, inadvertently provides evidence linking the bomb used to the Syrian government.

The diagram published by the Russian government of the M4000 munition provides multiple matches to the debris recovered from the Al-Lataminah attack, linked to the munition used in the Khan Sheikhoun attack by the presence of the same filler cap. First, it is possible to establish the size of the munition remains are consistent with the size of the M4000 munition. In the OPCW-FFM report on Al-Lataminah the remains of the tail section of the munition, with one tail fin still attached, is measured as 900mm wide. Based on this it is possible to calculate the approximate circumference of the munition. The below image shows this process in Blender:

Based on the above measurements the diameter of the munition is approximately 458mm, and considering the level of distortion to the remains of the munition this is consistent with the 460mm diameter of the M4000 chemical bomb. It is also possible to get an approximate measurement for the tail fins thanks to the following image in the OPCW-FFM report on Al-Lataminah:

This object is described in the OPCW-FFM report as follows:

“01SDS(B) is a large corroded and deformed metal object. Despite the corrosion, it is still possible to see layers of dark green and grey colour. It is also possible to see a smaller inner ring in the middle, linked by seven metal parts to a larger, outer ring. Four of the parts that are linking rings are rectangular. The other three are much larger and triangular. The spacing between the three parts, in addition to indications on the rings, point to one missing larger triangular part.

This is consistent with an aerial bomb tail fin assembly.

The FFM took numerous measurements of this item. Given the level of deformation, these measurements are only approximate dimensions. These approximate dimensions have not been included.”

Based on the visible measurement, it was possible to recreate a 3D model of the tail ring, which again measured to approximately 460mm:

These measurements are consistent with claims made by experts consulted by the OPCW-UN JIM in their report on the Khan Sheikhoun Sarin attack:

“Examining the munition remnants observed inside the crater, the forensic institutes and individual experts concluded that the remnants were pieces of a thin-walled munition of 300 to 500 mm in diameter and were likely from an aerial bomb.”

The design of the tail section and tail rings are also consistent with the diagram of the M4000 bomb, showing the tail fins do not extend beyond the sides of the tail ring, and the tail section does not extend fully into the tail rings, as it does on some other models of bombs, including the MYM6000.

Also recovered from the impact site of the Al-Lataminah attack were the aforementioned identical filling caps, matching the type recovered from the Khan Sheikhoun attack. In the OPCW-UN JIM report on Khan Sheikhoun the cap recovered was described as “uniquely consistent with Syrian chemical aerial bombs”:

One cap has a piece of metal attached to it which itself is attached to a suspension lug, used to attach the munition to an aircraft. Two caps are also visible on the side of the munition in the M4000 diagram, one of which is positioned close to a suspension lug:

Visible on the front of the bomb in the above diagram is the fuze and fuze housing. The fuze housing, which is separate from the blue coloured front end of the munition, extends over the front edge of the munition, and this would be consistent with debris recovered from the Al-Lataminah attack site:

The OPCW-FFM specifically refers to this as a fuze, and based on markings on the fuze it is possible to identify it as a a Russian АВУ-ЭТ impact fuze:

“09SDS is a heavily deformed and damaged metal object. On the both sides threads are visible. This part also bears visible markings which point to a universal bomb fuse. The fuse has been activated and does not contain explosive material. This device is normally electrically armed, heat resistant, and can function as point detonating or with delayed action. It is used on a large number of aerial bomb types by numerous nations.”

The thread indicates the fuze housing would have been screwed into the front of bomb, consistent with the diagram of the M4000 chemical bomb. The fuze detonates a 3kg charge that runs through the front half of the munition, marked in red.

Also recovered from the Al-Lataminah attack site is the remains of a heavy metal object that is consistent with the thicker front end of the bomb marked in blue in the above diagram:

The OPCW-FFM report describes this object, including the following sentence:

“One side of the item is flat with only the bottom part bearing marks of violent splitting.  Sides of the larger object are uneven and rough, probably the result of violent separation as well.”

Its position around the fuze and bursting charge would be consistent with the damage seen on the object, and it is the only object with these heavier dimensions recovered from the attack site.

Another type of object recovered from both the Al-Lataminah and Khan Sheikhoun attack sites are metal rails with equally distributed holes:

Top – Khan Sheikhoun; Bottom – Al-Lataminah

The rail recovered from Al-Lataminah is approximately 550mm long, with broken bolts inside some of the holes, and a 5mm metal layer attached, the thickness of which is consistent with other metal layer debris recovered from the impact site. It is likely this was used to attached parts of the bomb together, and it seems certain to be one the objects marked in grey in the below diagram:

One of the most interesting items is in the rear of the bomb, marked as a “mixing arm”. Part of this, found in the very rear of the bomb, was recovered from the scene of the attack:

The shape of the object can clearly be seen in the rear of the diagram, and the outer side of the object has a visible broken metal rod:

This is described in the OPCW-FFM report:

“The lid part has a larger hole in the middle where a segment of a protruding metal rod (labelled 3) is visible. The metal rod is broken and deformed.”

This, again, appears consistent with what is visible in the diagram of the M4000 bomb.

Due to the total lack of public documentation about these munitions prior to November 2nd, the Russian government’s presentation on Khan Sheikhoun has made it possible to make these matches, further providing information about the Syrian government’s role not only in the Khan Sheikhoun Sarin attack but also in the Al-Lataminah Sarin attack.

The only way for the Russian or Syrian governments to now deny the M4000 bomb was used is to produce detailed photographs of the M4000 bomb, showing the same parts indicated above, or, if the Syrians still claim all these bombs were destroyed after 2013, declassify and publish further information about the bomb.


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  1. Thomas Peterson

    Have any named international weapons experts endorsed bellingcat’s sensational scoop?

    Has anyone in the media such as the NYT or The Guardian picked up the story?

    Why haven’t they, if the proof is solid?

    • DDTea

      Because nobody cares about atrocities in Syria anymore. Another

      Congratulations to Assad and Putin for renormalizing chemical warfare after decades of prohibition and revulsion.

      • Austin Rock

        That is a very lame excuse, because nobody cares! The US fired cruise missiles long before a proper finding was even made. The US and its media railed against the bombing in Aleppo and remarkably silent over Raqqi, the East of Aleppo looks now remarkably like Raqqi. So if you politicise arguments especially scientific ones like this you leave yourself open to charges of bias. The US has an agenda against Russia and will make up any kind of thing to justify it. That is why (in Europe) most people don’t care, we’ve heard this demonising before remember Colin Powel’s Mobile Scud launchers in his WMD presentation before UN.

  2. Kline

    Even if Syrian regime has destroyed all its declared M4000 bombs in 2013, it had enough time (3-4 years) to rebuild other M4000 bomb.

    Don’t forget that regime produce a lot of its own ordnance. Syrian regime only need the plan to continue to produce this model of bomb.

    • Thomas Peterson

      The problem is that the fragments found dont covincingly match such a bomb.

      Of course there could be an imaginary bomb, as you suggest.

      Kind of like Santa Claus.

      • DDTea

        Actually, they do convincingly match such a bomb in the case of Ltamineh and the M4000.

        Nothing mismatches in Khan Sheikhoun, but very few remains of the device are available to comment on. The story there is in the residues and fantastic chemical forensics, namely [PF6-] and hexamine.

          • oui oui

            how can you say this sarin binary
            in the first picture of this article you can see two configurations for MYM6000 , one with the separation and two liquids , one without and one liquid , but the two with the item marked “mixing arm”
            and the M4000 is shown with no separation and one liquid
            how can you say if the separation was there or not , it would have been fixed on this rail
            how can you say if the “mixing arm” has been used

        • Thomas Peterson

          And no the bomb remnants cannot be said to ‘match’ an M4000.

          You cannot match bomb parts using just a line drawn schematic of a bomb.

  3. Joerg Heinrich

    What do we know about the Syrian Chemical-Weapons-Programm?

    Well that every expert from end of 1990 up to 2013 did tell that it has the focus on “real” binary (Sarin)Weapons-Systems, see articles from FAS, israeli Ex-Militaers, french officels, defence-jornals [1] to [4].
    (binary-Weapon-System with the meaning of mixing in warhead in flight or direct bevor)

    And what did we see in Syria?

    The weapons-systems with sarin were not binary — course otherwise the must be some acid salt in the samples — for example isopropylammonium bifluoride if isopropylamine had been used as the acid scavenger.

    And the sarin was not suitable for “log term storage” — meaning from a Di-Di-Process and extra purified (like most US or “Russian” Sarin Weapons).

    But only this to “kinds” of weapon-usable sarin are know “binray” with “mixing in warhead” or “log term storage” suitable.

    So if the sarin that was found was “binary – mixed” and than badly purified but surly not for “log term storage” — it does not fit to “good-quality” weapon.

    It fits to a improvised weapon-system — more typical for terrorists.





    • DDTea

      Why do you assume terrorist sarin would be less pure than state sarin? Aum shinrikyo’ sarin was 90% pure while Iraq’s was only 50% to 60%.

      • Joerg Heinrich

        If you see an more detailt Reports you will find out that:

        1.) Aum shinrikyo reaches 90% once or twice — but regularly not

        2.) Aum shinrikyo sarin for the Tokio-Underground-attact had an estimated purity of 20% to 30% — not more

        3.) “military grade” sarin for “log storage” as ready to use agent inside the warhead has around 99% purity an is often distilled to reach such purity .

        4.) Iraks sarin-weapons had extrem problem with storage — after a few weeks or some months the sarin decompose so strong the weapos become useless.

        5.) Irak used its weapons immediately after production in the ongoing iran-irak war. — But the iraki – “short-live-strorage” can not be seen as a “real” Sarin-Wepons-System”-Technology.

        6.) Irak also startet to develop and produse “binary” weapon-system — course ther “short-live-strorage” –systems are nearly military useless.

        7.) an 155mm (or 152?) binary Atellery-Sarin-Shell has startet production bevore 1991 in Irakt

    • Kostja

      The JIM-report confirms that the Sarin in Khan Sheikhoun was produced by the binary route, using hexamine.

      “Moreover, the results confirm that sarin was produced by the
      binary route, in which DF is combined with isopropanol (iPrOH) in the presence of

      Your assesment of what is a “real” binary weapon and what is not simply lacks any scientific evidence.

      In fact, it is now proven that this Sarin was produced using DF from the Syrian stockpile which was produced in a “sophisticated” way. So this perfectly matches your sources claiming that the Syrian program was pretty advanced. Non-state actors would never be able to produce DF that way without decades of preparation.

      All of this is included in my source, see Annex II, “chemistry”.

      • Joerg Heinrich

        As i said:

        Sarin binary “prodused” (DF + isporopanol — no Di Di -Process) und in someway “neutrelices” and “purifeid” for short storage.

        And this ist not know as as “working” weapons-technoligy and do not pint to an military attack useing military weapons.

        Even more.

        It ist not proven that the DF ist from any syrian military source, the hexamine do not truly point to the government, to cite Mr Sellström [1] (chef of the OPCW-Mission in Syria):

        From: Åke Sellström
        Sent: Monday, June 16, 2014 9:44 AM
        Subject: SV: An Inquiry Into a Small Technical Matter

        Dear Professor Postol,
        The presence of hexamine may mean that this substance was used as scavanger for protons when producing sarin.
        It is a product simple to get hold of and in no way conclusively points to the governement. In addition hexamin found in samples may be derived from other sources for example, explosives.

        All the best
        Åke Sellström

        And some analyses shows that hexamine is not good appropriable as acid-stravange in a binary sarin reaktion [1].

        Sellström ones says it may has been used for stabilisation [2].

        Hexamine maybe points to a link between the 2013 goutha-attack an this attac in april 2017 — if we assume the hexamine comes from the the same “sarin- technique”.

        But Videos from 2013 shows that “rebels or terrorists” use volcano-rokets with chemical agents [3] [4] [5].

        So if the goutha-attack was a terrorist attack — hexamine points to the terrorsits






        • Kostja

          The Sarin used in this attack was definetely produced using the Syrian chemical weapons program. The OPCW took reference samples from the Syrian DF in 2013 and identified certain impurities that show a sophisticated way of producing DF using HF along the way.
          The marker chemicals proving that are not Hexamine, but PF6, isopropyl phosphates and isopropyl phosphorofluoridates. The FFM says:

          “The presence of marker chemicals that are believed to be unique is a strong
          indication that the sarin released in Khan Shaykhun, as well as in previous
          incidents, was produced using DF from the Syrian Arab Republic stockpile.”

          and also:

          “The use of HF indicates a high
          degree of competence and sophistication in the production of DF and points to a
          chemical-plant-type production method.”

          We also know for sure that hexamine was again present. So the use of Hexamine is completely consitent with the use of a very sophisticated process of producing Sarin, and also appears to be a uniquely Syrian method. Additionally, we know for a fact that Syria declared Hexamine as a component of it´s binary weapons arsenal (explicitly).

          So this is damning evidence that

          1) Hexamine was in fact used as a component of the Syrian production method.

          2) This is no contradiction to an advanced weapons system.

          3) The Sarin was not mixed during the flight but rather before use.

          So, as a conclusion, allthough it´s not definitive proof, hexamine strongly indicates that Syria is responsible for both attacks.

          The other marker chemicals prove that Syria is responsible for Khan Sheikhoun.

  4. Thomas Peterson

    DDTea – November 15, 2017
    Not actually true, and i’ve already explained why.

    Like I said, I don’t believe you. Nobody has hitherto made any mention of an extra amine being required to catalyse the Sarin reaction in a binary munition other than you.

    It definitely isnt necessary for acid removal in such a device seconds before deployment. The acid simply doesnt matter on such a short time frame.

    • Kostja

      Why are you talking about binary munitions? Binary munitions are not what the Syrian program consists of. Also, there is a fuction for an amine even in a binary munition. The DF-Isopropanol reaction is a chemical equilibrium. This means that if you reduce the amount of products, the product reaction will be enhanced (Le Chatelier´s principle). So, by binding HF, you enhance the product reaction and increase the amount of Sarin you produce. This is useful even in a binary munition.

      However, the Syrian program did not rely on that technology. Components were mixed before use.

  5. Thomas Peterson

    “Also, if not treated with a base in situ, the hydrogen fluoride generated by sarin production can build up enough pressure to burst the bomb casing before it reaches its target.”

    Nonsense, the HF would be in solution. The bomb is full of liquid.

    • DDTea

      You can’t determine that a priori. If you can, then show me your calculations. It depends on the solubility of HF in the product mixture, which varies with temperature and pressure. This is data that is determined experimentally and isn’t readily available publicly.

      • Thomas Peterson

        youre clutching at straws now.

        look, the bomb is not going to prematurely explode just because some HF forms for a few seconds in a bomb that is already full of liquid.

        it’s not worth considering because it wouldnt happen.

    • Joerg Heinrich

      You say:

      “Nonsense, the HF would be in solution. The bomb is full of liquid.”

      Thats wrong.

      All Liquids are sarin, DF, Isopopanol — an HF would not get in a solution with any of them.

      Insted it will react immediately and “destroy” lots of the sarin or DF or Isopropyl–alkohol.

      There are only an few chemicals that are more reactive the HF-gas.

      • Thomas Peterson

        No, actually it takes months for HF to significantly degrade Sarin, this is well known.

        And yes it would be in solution otherwise there would be no need for acid scavengers in normal Sarin production. You could just vent the HF.

        • Joerg Heinrich

          Thats extremly wrong.

          A Sarin solution in ph-neutral clear water has a “half-life” of around100 to 150 hours.

          If the water becomes light acidly the “half-life” drops to some few hours, if the water beomes alkaline the “half-life” can drop to some 10 minutes.

          For decontaminating purpose military uses soft soap with some stronger lye decomposing sarin within seconds or minutes.

          Please see some basics before writing:

          • Thomas Peterson

            wiki says: Sarin with residual acid degrades after a period of several weeks to several months. The shelf life can be shortened by impurities in precursor materials. According to the CIA, some Iraqi sarin had a shelf life of only a few weeks, owing mostly to impure precursors.

            which is fine, in a binary weapon we dont care what happens to the sarin in a few weeks, we are deploying it within seconds.

          • Joerg Heinrich

            to be more precise citation of the german Wikipedia (link see post before):

            In geman:

            Reines Sarin ist eine farblose, nahezu geruchlose, relativ flüchtige Flüssigkeit. Mit Wasser ist es in jedem Verhältnis mischbar. In Wasser zersetzt sich Sarin abhängig vom pH-Wert: Bei pH 7 beträgt die Halbwertszeit der Hydrolyse des Esters etwa 100 bis 150 Stunden; in saurer Lösung erfolgt die Zersetzung derselben Menge schon in zwei, in alkalischer Lösung in einer Stunde.[20]

            In english:

            Pure sarin is a colorless, almost odorless, relatively volatile liquid. It can be mixed with water in any ratio. In water, sarin decomposes depending on the pH: at pH 7, the half-life of hydrolysis of the ester is about 100 to 150 hours; In acidic solution the decomposition of the same amount takes place in two hours, in alkaline solution in one hour. [20]

            An the source is the civil defence of Switzerland writing:

            Hydrolysis (degradation in water)

            Half-life at 20 degrees Celsius


            0.6 min at pH 11
            80 hours at pH 7
            27 min at pH 1

            And you can read nearly the same Inforamtion in literatur and more “scientific” websites and databases , like:


            Or better:
            Thieme Medical Publishers — Römpp’s Chemistry Lexicon

  6. Thomas Peterson

    “Then why, in your view, did the US include isopropylamine in its binary sarin weapons?”

    wikipedia says to remove acid. maybe there was acid buildup in one of the precursors used. acid removal obviously would not be a priority if the acid only formed a few seconds before the device exploded, that’s common sense.

    • DDTea

      Read the article more closely. The isopropylamine was mixed with isopropanol, not with DF. DF is more likely to have residual acid from manufacture than isopropanol.

      Your intuition is wrong, and it perplexes me why you’re doubling down on this point.

  7. Thomas Peterson

    And obviously if HF was just going to burst out of our freshly prepared Sarin as a gas and not be in solution we wouldnt need acid scavengers really would we when making the pre-mixed version of Sarin.

    We would just vent the HF.

      • Thomas Peterson

        And again the article says the isopropylamine is there to bind HF, no other reason.

        But why? Just for a few seconds in flight? Seems pointless.

  8. Thomas Peterson

    Joerg Heinrich – November 15, 2017
    to be more precise citation of the german Wikipedia (link see post before):

    Your citations of German wikipedia are adding nothing.

    The citation of USA wikipedia by me says that it takes months to significantly degrade Sarin with residual acid.

    Prove that claim wrong.

    • Joerg Heinrich

      Facts are:

      Hydrolysis (degradation in water)

      Half-life at 20 degrees Celsius

      0.6 min at pH 11 (strong alkaline)
      80 hours at pH 7 (neutal)
      27 min at pH 1 (strong aciedly)

      (civil defence of Switzerland in german : Bundesamt für Bevölkerungsschutz BABS)

      And all the specialist literature writes the same, see pubchem if you have no acces to specialist literature.

      I am a trained engineer with basic (but solid) chemistry expertise and i have done parts of my national service in an (military) CBRN defense unit (Self-protection, decontamination Detect warfare agents).

      So please, do not bullshit me.

      • Maxy

        Wow, Joerg Heinrich, you really know how to counter arguments. Claim: “It takes weeks or even months for acid to degrade Sarin.” Answer: “Extremely wrong! Bullshit! Sarin is not stable in water!”
        But wait: Is this something new storing Sarin in water? (If the answer is yes, storing at pH7 is certainly a good idea. What do you think?) And I guess we can agree on that: It is of utter importance to ensure the CW rocket is absolutely – and I mean it: absolutely – waterproof?
        So, while your expertise in chemistry might only be basic, though solid, you have proven, in a most impressing way, that you are a true master in the field of logic. And, let us be forgiving: It is certainly the privilege of true masters to respond in an arrogant and rude way if someone dares to state (correctly) that the master’s citations “are adding nothing”, because they are absolutely OT.
        To sum it up: Yes, you are absolutely right, the biggest problem when dropping a Sarin bomb or launching an artillery shell filled with Sarin is water. Water here, water there, water everywhere.

        • Joerg Heinrich

          As am matter of fact sarin is very damageable by any kind of corrosive substance, independent if they are acidly or alkaline, see link in my older posts.

          An HF (Hydrogen fluoride) as a gas is much more “acedly corrosive” then as a solution in water, see the basics:

          Even after neutralization an purification the iraqi sarin had have an “half live” of only some weeks.

          “Sarin with residual acid degrades after a period of several weeks to several months. The shelf life can be shortened by impurities in precursor materials. According to the CIA, some Iraqi sarin had a shelf life of only a few weeks, owing mostly to impure precursors.”


          Even the “Bellingcat Expert” Dan Kaseza sees no possibility to build an binary weapon-system without a “good” acid-stravanger like Isopropylamine.

          • Maxy

            There’s just too much speculation.
            Theory (e.g. chemistry) is one thing, weapons technology is quite a different matter. While some persons can proudly present their expertise in chemistry (this is not meant as an affront to YOU), what does the public know about the technology developed and used by all those philanthropists? Not much, simply because the weapons programs with all their required experiments etc. are secret and the relevant information is classified.
            So you think the claim “A few seconds of HF doesnt matter” is bullshit and the claim “it will react immediately and “destroy” lots of the sarin making it useless as a weapon” is 100% true? Maybe, maybe not. Maybe it depends, above all, on how much HF GAS is being released? Who knows. But one thing is for sure: A lot of parameters are involved, there’s a lot of interdependencies and without knowing the results of the relevant experiments you can only – speculate, just like other persons like to do.
            By the way, thank you for providing good links.

          • DDTe

            This isn’t baseless speculation. Organic chemistry is a mature enough field, and the chemistry of sarin is well enough documented, that we can make strong predictions given just a few parameters. And this is worthwhile discussion because it has helped narrow the range of reasonable scenarios around these chemical attacks.

            That’s what I’ve been doing since 2013, and i’ve consistently been more right than wrong.

          • Joerg Heinrich

            to “Maybe it depends, above all, on how much HF GAS is being released? Who knows.”

            It is simple to calculate how nuch HF-Gas will bee released from the reaction.

            1 mol DF + 1 mol Isopropanol => 1 mol Sarin + 1 mol HF

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