the home of online investigations

You can support the work of Bellingcat by donating through the following link:

The OPCW FFM’s Report on the April 7th 2018 Douma Chemical Attack Versus The Open Source Evidence

March 1, 2019

By Eliot Higgins

Translations: Русский

The OPCW Fact Finding Mission’s new report on the April 7, 2018 Douma chemical attack provides more details about what occurred in Douma nearly a year ago — and also allows us to compare those details and their conclusions to open source evidence and statements made by various parties.

The Open Source Investigations

A few days after the attack, Bellingcat published an article, Open Source Survey of Alleged Chemical Attacks in Douma on 7th April 2018, examining the open source evidence surrounding the attack. This article focused on one location in particular, an apartment building which, according to Bellingcat’s analysis of the open source material, contained at least 34 bodies. A chlorine gas cylinder was found embedded in the floor of one of the building’s balconies, as seen below, indicating gas was expelled from the cylinder directly into the building:

The article concluded:

Based on the available evidence, it is highly likely the 34+ victims killed in the 1930 attack on the apartment building near al-Shuhada Square were killed as a result of a gas cylinder filled with what is most likely chlorine gas being dropped from a Hip helicopter originating from Dumayr Airbase.

A later article published by Bellingcat on April 29th, All the Pieces Matter – Syria’s Chlorine Bombs and the Douma Chemical Attack, examined the remains of the two chlorine bombs used in the attack, highlighting the metal frame found at each impact site that matched metal frames attached to chlorine cylinders in other chlorine attacks by Syrian government forces. In the Douma attack, one frame had become detached from the chlorine cylinder, but at the other attack site, the metal frame was clearly visible, still attached to the chlorine cylinder:

The New York Times and Forensic Architecture worked together on an investigation into the attack that was published in June 2018; One Building, One Bomb: How Assad Gassed His Own People included a detailed reconstruction of the attack sites produced by Forensic Architecture:

The New York Times and Forensic Architecture investigation confirmed Bellingcat’s earlier analysis, adding additional key details, such as reconstructing the badly damaged metal frame found detached from one of the chlorine cylinders and proving it would fit perfectly over the chlorine cylinder. Most notably, it identified markings on the chlorine cylinder documented at one site, which were consistent with it having hit a metal mesh structure as it fell onto the balcony with a metal mesh structure found near the chlorine cylinder, fitting perfectly with the markings on the cylinder. This further confirmed the chlorine cylinder had been dropped from the air, not placed at the scene as some had alleged.

While Bellingcat stated in its reporting that chlorine was highly likely to have been used in two attacks that occurred at 1930 local time, some reporting on the ground suggested otherwise. Reports from the documentation group the Syrian Network for Human Rights and the Violations Documentation Center referenced both the 1930 attacks, and an earlier suspected attack at 1600 near Sa’da bakery in Douma. In addition to allegations of chlorine use, the VDC reported witness statements describing symptoms that suggested another chemical agent could have been used:

Dr. Jamal Rafie (pseudonym), told the VDC that the symptoms that he saw on patients “do not resemble chlorine attack symptoms. Chlorine alone cannot induce such symptoms because while it does cause suffocation, it does not affect the nerves. There were symptoms indicative of organic phosphorus compounds in the sarin gas category. But the smell of chlorine was also present in the place.”

Dr. Mohammed Kuttoub from the Syrian American Medical Society (SAMS) told the VDC that his colleagues in Eastern Ghouta saw symptoms on people that include: “pinpoint pupils, slow heartbeat, slow breathing, heavy foaming from the mouth and nose, and the burning of the cornea in some cases.”

Syrian Civil Defence, also known as the White Helmets, reported that a chemical attack at 1945 on April 7, 2018 killed more than 43 people and injured over 500. They reported that the dead victims displayed signs of cyanosis (a bluish discolouration of the skin), excessive oral foaming and corneal burns. Six living casualties were reported to have pinpoint pupils and convulsions. The report concluded the casualties had been exposed to “toxic chemicals; most likely an organophosphate element.”

There’s no indication that these conclusions were based on anything but observations of the victims’ symptoms, and it’s possible the severity of the chlorine exposure was responsible for the unusually strong symptoms, as described by Keith B Ward for Bellingcat in The Lethality of Chlorine Gas – A Possible Explanation for High Casualties and Deaths Following the April 7, 2018 Attacks in Douma. 

The OPCW FFM Report

The OPCW Fact Finding Mission (FFM) seeks to establish whether or not the use of chemical weapons is likely to have occurred, not to establish who was responsible for attacks. Therefore, while the Douma report provides many additional details, it does not go beyond establishing that an attack had occurred. In the summary of the report it states:

Regarding the alleged use of toxic chemicals as a weapon on 7 April 2018 in Douma, the Syrian Arab Republic, the evaluation and analysis of all the information gathered by the FFM—witnesses’ testimonies, environmental and biomedical samples analysis results, toxicological and ballistic analyses from experts, additional digital information from witnesses—provide reasonable grounds that the use of a toxic chemical as a weapon took place. This toxic chemical contained reactive chlorine. The toxic chemical was likely molecular chlorine.

Unlike many of the OPCW FFM’s previous investigations, the OPCW FFM team was able to directly collect samples from the attack, ensuring full chain of custody. Based on those samples, and other evidence, the OPCW FFM was able to draw the above conclusion.

What’s of particular interest in relation to the open source investigations is the documentation and analysis of the impact sites by the OPCW FFM, where much of the open source video and photographic materials were recorded. The report identifies four locations of interest, two of which are the balcony and bedroom impact sites.

Location 2 is identified as the balcony site, with the location described in the report matching that of the geolocated open source images of that site. The OPCW FFM report includes a diagram of the building, indicating where bodies were recorded by locals in the aftermath of the attack:

The OPCW FFM team were only able to visit the building after the bodies had been removed and buried, so were unable to examine the bodies themselves. The report states:

Many of the signs and symptoms reported by the medical personnel, witnesses and casualties (as well as those seen in multiple videos provided by witnesses), their rapid onset, and the large number of those reportedly affected, indicate exposure to an inhalational irritant or toxic substance. However, based on the information reviewed and with the absence of bio-medical samples from the dead bodies or any autopsy records, it is not currently possible to precisely link the cause of the signs and symptoms to a specific chemical.

While the OPCW FFM report does not provide its own casualty figures, it does include statements from witnesses regarding the number of dead:

Witnesses reported to the FFM team that there were 43 decedents in relation to the alleged chemical incident, most of whom were seen in videos and photos strewn on the floor of multiple levels of an apartment building and in front of the same building. Additionally, several witnesses reported seeing decedents in the basement of the building, on multiple floors of the building, on the streets and inside the basements of several buildings within the same area.

The initial Bellingcat investigation into the incident counted at least 34 bodies in videos and photographs from the balcony site. As there was no footage of the basement of the building it was not possible to count any victims (if any) that were killed in the basement.

The OPCW FFM analysis of the balcony site provides additional confirmation that the munitions used were air dropped. The OPCW FFM was able to access the site, and took multiple photographs of the gas cylinder and surrounding area:

The report notes the following:

The mangled ironwork present on the patio indicated that there would have been a metallic frame and mesh covering it at one stage, though it was not clear whether this would have been present at the time of the alleged incident or had been demolished prior to that. The visual damage on the body of the cylinder indicates that the lateral aspect of the cylinder did not slide on the mesh but it hit perpendicularly.

This statement is consistent with the work of Forensic Architecture and The New York Times, which had previously noticed the damage on the cylinder caused by striking the mesh:

In the above image, Forensic Architecture had recreated the site as a 3D model, including a textured model of the cylinder, and the metallic frame and mesh. It was possible to then compare the model of the mesh to the markings on the model of the cylinder, and demonstrate they matched in size and shape. The OPCW FFM report adds more weight to the argument that this was a result of the cylinder being dropped onto the balcony.

In addition to the cylinder striking the mesh as it fell, the OPCW FFM presented evidence it struck another object:

Observing the damage on the roof above the crater, the experts were able to provide an explanation of the cylinder not penetrating completely through the aperture. It can be seen that there was a large impact on the roof and walls above the balcony. The impact would decrease the velocity of the falling cylinder and changed its trajectory while hitting the concrete floor of the balcony causing a hole in it, but without sufficient energy to fall through it.

The damage described above can be seen in images taken by the OPCW FFM during their visit to the site:

To further check this theory, the OPCW FFM had experts analyse the likely pattern of damage to the cylinder if it had struck the corner of the building. The resulting analysis showed the damage to the cylinder was consistent with this type of impact:

The OPCW FFM also documented changes in the locations they investigated from the footage filmed after the incident and what they found during their visits. In the case of the balcony site, they noted the cylinder had been previously sampled, objects and debris had been moved, and most significantly “the metal frame and fins, visible on the terrace in videos, were missing at the time of the FFM visit.”

The metal frame and fins are one of the key pieces of evidence connecting the cylinder found at the balcony site to the other gas cylinder at the bedroom site, and previous chlorine attacks in Syria. At the time of the FFM visit, the site was under the control of pro-government forces.

As with the balcony site, the impact and trajectory of the gas cylinder at the bedroom site was carefully examined by the OPCW FFM, with experts asked to assist with the analysis. The bedroom site has caused particular controversy, as the position of the cylinder on the bed, some distance from the hole in the roof it had apparently made, led some to claim the cylinder has been placed onto the bed manually by unknown actors. However, the OPCW FFM report stated the following:

The team consulted experts in mechanical engineering, ballistics and metallurgy to provide qualified, competent assessments of the cylinder trajectory. The results of these assessments indicated that the shape of the aperture produced in the modulation matched the shape and damage observed by the team. The assessments further indicated that, after passing through the ceiling and impacting the floor at lower speed, the cylinder continued altered trajectory, until reaching the position in which it was found.

The simulation of the impact also shows that the shape of the hole in the roof is consistent with the gas cylinder landing parallel with the ground, as demonstrated in the below image:

A computer model of the cylinder after impact was also created:

The flattening of one side of the cylinder can clearly be seen in photographs of the gas cylinder:

This, again, clearly indicates that the chlorine gas cylinders used in the attack were dropped from the air, with modifications to those gas cylinders consistent with those seen on gas cylinders used in other chlorine attacks. If these scenes were faked, as some have claimed, then they would have to have faked them in such away that when experts examined the damaged gas cylinders from each site they were perfectly consistent with the types of impacts seen at each site. This includes a metal mesh pattern on one cylinder, along with damage consistent with it hitting the corner of the building, and the other cylinder landing in a very different way, parallel to the roof it struck, causing one side to flatten.

While some may find comfort in increasingly elaborate conspiracy theories about what happened in Douma, the OPCW FFM report continues to make it clear that the Douma attack was yet another chlorine attack delivered by helicopter, using the same type of modified gas cylinders as seen in previous chlorine attacks.

Bellingcat’s research for this publication was supported by PAX for Peace.

Eliot Higgins

Eliot Higgins is the founder of Bellingcat and the Brown Moses Blog. Eliot focuses on the weapons used in the conflict in Syria, and open source investigation tools and techniques.

Join the Bellingcat Mailing List:

Enter your email address to receive a weekly digest of Bellingcat posts, links to open source research articles, and more.


  1. Non

    Well, for Russian officials someone’s tweets has more weight and this particular OPCW report is just another example of Western conspiracy against Russia or as in this case, against their ally.

  2. francesca

    Surely the OPCW team would have been able to do post mortems on the dead and determine damage (burns and scarring )to the lungs and upper airways typically caused by chlorine gas inhalation (at fatal concentrations)
    Also cardiomegaly can be found post mortem, as well as corneal burns and injury to the conjunctiva
    Survivors can show the results of toxic chlorine gas inhalation via xray or visible damage to the eyes for quite some time after exposure.
    I am surprised that this lead does not appear to have been followed up, and also wonder why no attribution has been made in the final report, as the OPCW is now mandated for that

  3. francesca

    It seems rather convenient that the bodies have been “disappeared”
    There appear to be witnesses to the deaths, after all, someone took the videos, but no witnesses to burials?
    Come on Bellingcat, where are your open sources now?
    Never mind, there were still survivors who could have been tested for the effects of chlorine gas

    • Servus

      “francesca” – do you have to pay a penalty for changing a compromised pseudonym? This one has been used previously by a Russian troll . Did you intend to enter all 3 notes with the same pseudonym or did you forget how to use multiple windows in your tool, or is it another bug in your software?
      Hope none of your “friends” denounces your sloppy work, they treat you like a dog, and you have to pay penalties for every sidestep.

      The answers to your questions are in the B?cats article and OPCW report, BTW, are you allowed to read these or just translate the ready made text given to you by your supervisor ?

      BUT shortly, OPCW made their inquiry (and not without difficulties and two weeks delays), under control of Syrian army with the Russian military police in the background. And could visit sites and talk to people under direct supervision.

      So this is the explanation why they were unable to do the analysis you accuse them for not doing. Anyway, you guys are very predictable and accusing the report for what it was not intended to do, like attributing the attack, is your standard tactic.

      You should hide your identity better, suggested pseudonyms ‘francesca1″ etc.

  4. Wirplit

    I seriously wonder how much reliance can be played on the SCD ( White Helmets) who clearly had an agenda as has been shown repeatedly and might be assumed given its origins and funding. I feel this source should not be used.

    • Servus

      “assumed given its origins and funding” , c’mon, don’t be shy, it’s MI6 and Soros with reptilians funding!

      • Mad Dog

        Soros is everywhere, even funding the AntiFas and others in the US, but I have no idea about his reptilian army!

    • Jeroen

      One seriously wonder how much reliance can be given to Foreign Minister Lavrov or Russian defense speakers who tried to spin that “no chemical attack took place”?
      Did they clearly have an agenda? I feel those sources should not be used.

      So where is the Russian Report of those Voiska RChB troops who examined Douma after 7 April, or those Russian Reconciliation Center guys who were there April 9th?
      For that matter also where is the full and final Russian report on the “alleged rebel lab/warehouse” in Douma? Surely with so much evidence please provide us with those reports both, so that any critical thinking human can compare all three.
      Where is that similar chlorine canister Alexander Rodionov reported present in that “lab/warehouse” for example?
      I guess all Russian journalists like from Tass, Rossiya-24 and others now demand publication of those full reports?

      Or they don’t,
      because of certain reasons?

    • Jeroen

      The White Helmets clearly have an agenda?
      Indeed, medical evacuation, urban search and rescue, rescueing wounded people from danger areas and bombed buildings.

  5. Mr.Bushkin

    Chlorine cylinders dropped from the air or perhaps used as part of “Volcano” IRAMs ( ) look rather as follows:

    And in the uncut original video from Douma there is no deformation of the chlorine cylinder at all:

    • Servus

      “Chlorine cylinders dropped from the air or perhaps used as part of “Volcano” IRAMs”
      Well, not likely. All IRAMs have an opening at one end, where the “nozzle” or, exhaust of the rocket engine is located. None of the discussed cylinders have one so, these are for sure “dumb gravitational bombs”, which is also consistent with reports of the presence of the aircraft prior to the attack.

      There were more then one cylinder dropped in Douma, so be sure to compare the images of the same one. Can’t locate video in the link you have provided.

      • Mr.Bushkin

        You must press “Show” to the right of the inscription: “This medium could contain sensible material.” in order see the original video with a complete view of the chlorine cylinder.

        The second chlorine cylinder is indeed deformated, but not to the degree as I would expect from looking at HRW documented ones.

        • Servus

          The photo you show is not from the site investigated by OPCW and Bellingcat.

          Anyway, the Forensic Architecture made simulations of impact analysing deformations that matched the observed deformation so, they must have a pretty good idea about the cylinder’s and the armed concrete’s mechanical characteristics. In the view of the videos directly after the attack , with one cylinder still decompressing, the serious damage to the roofs in both cases, witness reports, OPCW and FA analysis, all supporting the idea that cylinders fell from the air and seriously damage the concrete structures, it’s difficult to think that something different happened. Unless of course you have some new and very reliable information, which you don’t.

          “don’t seem to ” well, the cylinders found in Douma are the proof that something difficult to imagine can happen.
          Unless you come with something new about the discussed sites, it’s the end of discussion for me.

          • Mr.Bushkin

            That’s obviously not a photo but a video with a reference chlorine cylinder in a realistic condition after the impact on the ground, allowing the observer to judge about its mass and its robustness.

            And such a chlorine cylinder will obviously hardly break through concrete without taking no damage in case of the first cylinder from Douma or barely any damage in case of the second cylinder from Douma.

          • Servus

            There were many different containers used over the years, some had even labels from their manufacturers, so one can not know if a cylinder from some other side says anything about the Douma case, this is nonsense.

            I’ve seen many pictures of dropped cylinders, some are flattened out or broken in pieces some are almost intact. There are just too many differences between the situations so a reasonable person can not draw conclusions you make.

            If you really care, go and ask the AF for their simulation parameters, and verify that these realistically describe the involved materials.

            Also, please read the full OPCW report it carries many details that are relevant to your doubts.

          • Mr.Bushkin

            Well, the condition of Douma chlorine cylinders under consideration of the weight, robustness and internals of reference chlorine cylinders strongly counterindicates the version about them being dropped from the air, while I also would not expect that version to be explicitly formulated in the OPCW report either.

          • Servus

            You are dropping your conclusion from the air, there is no substance to your argument, just opinions while I showed you how to go about finding facts.
            But it needs some work and competence.

            The only thing you says is: “I can’t imagine it happened the way all evidence shows it happened.” It’s hardly the fault of facts….

            You admit to not reading the OPCW report… this is not serious.

          • Mr.Bushkin

            “[…] OPCW and FA analysis, all supporting the idea that cylinders fell from the air […] Also, please read the full OPCW report it carries many details that are relevant to your doubts. […] You admit to not reading the OPCW report… this is not serious. […]”

            LOL, you must be kidding me, since the OPCW report does not state anything like this and even speaks about “alleged incident”:

            “3. The aperture observed was circular in shape with approximately 45 degrees angular edges.
            4. The mangled ironwork present on the patio indicated that there would have been a metallic frame and mesh covering it at one stage, though it was not clear whether this would have been present at the time of the alleged incident […]
            5. The FFM team noted that a similar crater (see photos below) was present on a nearby building.”

          • Mr.Bushkin

            Oh, I almost forgot:

            The “3. The aperture observed was circular in shape with approximately 45 degrees angular edges.” in the OPCW report indicates that the impact causing the crater came from the floor below.

          • Servus

            Great stuff, keep reading, you are now at point 3, the point 7 says explicitly about falling (downwards and hitting first the roof , not the other downwards as you suggested)

            “7. Observing the damage on the roof above the crater, the experts were able to provide an explanation of the cylinder not penetrating completely through the aperture. It can be seen that there was a large impact on the roof and walls above the balcony. The impact would decrease the velocity of the falling cylinder and changed its trajectory while hitting the concrete floor of the balcony causing a hole in it, but without sufficient energy to fall through it.”

            I’m disappointed, for a moment I though you were into a sophisticated and rarely used argumentation techniques well explained by the Cohen brothers in the film “The Man Who Wasn’t There ” , but anyway, thanks, it allowed me to think it through and understand how to argue against it.

          • Mr.Bushkin

            To me it looks rather like an unrelated regular logistics hole for street and house combat, like the one on the metioned “building nearby”, created from the floor below, as indicated by the direction of the 45° angle. 😀

  6. Shawn Pelletier

    In the video of the canister on the bed. Can any explain how the canister hit the roof on its side while the metal fin harness was still attached? From what I understand that harness should have made the canister hit nose first into the roof. Also after going through the roof why was there so little damage to the harness while the one that did not completely go through roof had it’s harness totally mangled. Also why do the fins appear on the canister in older images but not the newer ones.

    • Eliot Higgins

      I’ve seen examples of barrel bombs becoming unstable and start spinning, so it *might* be what happened here. I can’t think of another explanation, but I’d be interested in hearing what others think.

      • Mad Dog

        Eliot, Eliot, you surely know that all those videos have been Photoshopped by the White Helmets under the direction of George Soros in order to discredit the Soviet Union (oops, I forgot). We should all overlook the lack of final reports by the Russian Federation because, as Trump has repeatedly said, I trust him (Vlad the neo-impaler). Will any of these players be brought to justice?

  7. concerned citizen

    Same old nonsense, no proof whatsoever these rusty old chlorine cylinders were ever dropped from a helicopter.

  8. JoseR

    Now that a leaked report from within the OPCW contradicts the official narrative that mad Assad did it, what’s your position on this? It seems your analysis are just propaganda after all, I am starting to doubt you guys even on the downing of MH17. Show some balls and tell the truth you puppets!!


Leave a Reply

  • (will not be published)

You can support the work of Bellingcat by donating through the following link: