Creating Impact: A Year On Stop Child Abuse —Trace An Object

Europol is currently in possession of more than 40 million images of child sexual abuse from around the world. In June 2017, it launched a crowdsourcing campaign called Stop Child Abuse—Trace An Object. Censored extracts from explicit images are regularly published on their website and members of the public are asked to help in tracing their location or country of origin.

These tips are then used to inform a competent law enforcement authority to further investigate the lead and to assist in the identification of the offender and the victim.

As of 23 January 2020, Europol has received more than 24,000 tips which have led to the identification of ten victims and the prosecution of two offenders. 

After a series of detailed reports in 2019, we are publishing three short case studies to explain the clues and methods which led us to track down an advertising flyer for Burger King in Mexico City, a sports arena managed by the Lions Club in Panama, and an industrial chimney stack in northern Moscow (See Figure 1).

We will offer a summary of our contributions towards the campaign throughout last year. We will also discuss the results in the context of a growing network of everyday citizens and researchers supporting the campaign as well as the impact this creates in the faster identification of victims, and the elimination and prevention of online abuse.

Finally, we outline a set of recommendations for Europol to improve engagement with the public and help sustain the campaign over time.

Figure 1. Image G19, G23 and G4 as originally listed by Europol


Case Studies

In the following sections you will find a selection of three investigations with details not previously included in our recent reports:


The Burger King Flyer — Mexico


Figure 2. Image G19 as listed by Europol. Several texts on this flyer were in Spanish or Portuguese and likely advertising some sort of delivery services

We identified a motorbike and a rider on the flyer featured in Image G19. 

In analyzing the flyer, we noticed several words written in Spanish or Portuguese. After translating and interpreting the broken messages, we believed the flyer was likely advertising some sort of home delivery service, the payment methods available, and a telephone number. 

The word “KING” led us to the food franchise BURGER KING (BK).

Mexico had the largest number of BK restaurants in Latin America in 2013, and had 430 stores in 2019. Being one of the largest markets in the region, it was possible that some sort of delivery services could have been offered in the busiest cities.

After checking different sources, a video on YouTube showed a BK advertisement for food delivery services in Mexico City. Checking the 2014 Google street view for the Mazaryk BK branch, it was determined that the telephone number advertised on the flyer was 1-454-KING (5464). 

This number appeared for the first time on BK’s website in July 2013 and was used by approximately 46 shops in the State of Mexico as well as Mexico City. 

Figure 3. BK branch Mazaryk, Mexico City in May 2014. A home delivery service is advertised on a banner. The colour scheme, wording, telephone number, icons, and motorbikes match all elements identified on Image G19

Another version of the flyer was found on social media but linked to a BK branch in the State of Michoacán in November 2013. Although the telephone number is different, this flyer largely matches Europol’s Image G19 (see Figure 4). The image of the rider on the bike was also used for a previous BK campaign design by a company called IDEATONICA.

Figure 4. A flyer sample found on social media and dated November 2013, according to the receipt in the background. The flyer belonged to a BK branch in Michoacán, Mexico. The design is almost identical to Image G19

Although the telephone number 1-454-KING (5464) continued to be displayed by some of the restaurants until at least 2019, most started displaying new numbers for the delivery services as the stores were upgraded between 2014 and 2015. See the example shown in Figure 5 for an illustration of the changing advertisements and phone numbers for BK delivery. 

Thus, it is very likely the flyer was produced between 2013 and 2015. 

Figure 5. An example of different home delivery numbers for one BK restaurant in Mexico City between 2011 and 2015. The banner styles change as the brand is modified



A Baseball Stadium — Panama 


Figure 6. Image G23 (left) featuring a sports arena classified by Europol as being in Central or South America. When compared to the baseball stadium PNC Park in Pittsburgh, Image G23 looks much smaller in size even though the blue seats are almost identical

Image G23 was listed and classified by Europol as probably being in Central or South America. This image showed a partial view of a sports arena with modern blue seats, but no numbering. Therefore, it was believed this was either a view of a practice field, a general admission section, or a stadium for an amateur league that did not assign seat selection for fans. 

We found an arena with almost identical blue seats: PNC Park in Pittsburgh, home to the Pirates. When comparing the roof structures and seat distribution, we concluded Image G23 was definitely a baseball arena, but likely much smaller than PNC Park (see Figure 6).

With baseball being one of the most popular sports in Latin America, there were a large number of stadiums to consider for this image. We listed five for each Latin American country with a tradition of baseball.

In Panama, a country where the sport is rich popularity, just adjacent to the massive Estadio Nacional de Panamá (“Rod Carew” Stadium), there is a smaller baseball stadium called “Leon Felipe Mota” (See Figure 7).

Sourcing different photos from Facebook and Google, it was clear the chairs, structure, the light tower and background terrain of this small facility were a perfect match as shown in Figure 7 and 8. 

Figure 7. Image G23 (left) is a section of the small stadium “Leon Felipe Motta” adjacent to the professional baseball stadium “Rod Carew”. The light tower and seat distribution largely match with Image G23

Figure 8. Blue seating, concrete flooring and red steel structure in February 2010 show a perfect match for Image G23

The small arena was inaugurated in the year 2000. 

According to local news from 2012, the property was managed by The Lions Club Panama, who have continued organising baseball tournaments for junior leagues in this facility according to their Facebook account.

After checking pictures of the stadium over the last 20 years, we noticed the steel structure changed colour from red to yellow at some point. The concrete steps were also changed to blue (See Figure 9). This redecoration took place between January and July 2015 and the colours have remained as such as of this article’s publication. Thus, Image G23 was most likely produced in or before July 2015.

Figure 9. Before January 2015 the steel structure was painted in red colour and the steps in plain concrete as seen on Image G23. However, from July 2015 until now, the steel structure was changed to yellow and some sections of the concrete to blue



The Russian Boiler House — Moscow, Russia 


Figure 10. Image G4 as published by Europol. A small tree on the image projects a shadow on the chimney stack

Image G4 was described by Europol as likely originating from a Russian-speaking country. 

To compare the architecture and structure of the building featured in Image G4, we gathered many images featuring old abandoned industrial buildings in the former Soviet Union, mainly in Russia. In particular, part of an old chemical plant in the Leningrad Oblast helped us to understand the type of architecture seen in Image G4.

We reverse searched this Leningrad factory in Yandex to find more buildings with similar characteristics. This process helped us to define the likely type of facility we were looking for: a district boiler house (котельная, or kotelnaya, in Russian). 

Looking for more clues, we noticed a small tree in the middle of Image G4, with a shadow projected on the chimney stack. With this information we estimated a solar elevation angle of approximately 57 degrees. 

Five cities were chosen as representative latitudes with a majority or sizable Russian-speaking population:  Saint Petersburg and Moscow in Russia, Minsk in Belarus, and Kyiv and Odesa in Ukraine.  

The solar altitude in Saint Petersburg never reaches the 57 degrees mark (not even in summer), so this city was not shortlisted. The next on the list was Moscow.

Using the term “котельная москва” (Boiler House Moscow) in Yandex led us to a perfect match for Image G4 in Wikimapia: a district boiler house in the Severny District of Northern Moscow. Further verification revealed that Image G24 was taken from an off-road small path located between the chimney stack and a row of garages adjacent to the boiler house.  

Figure 11. Image G4 was geolocated to a district in Northern Moscow. The child abuse material was produced an off-road path located between the chimney stack and a row of garages adjacent to the boiler house



A Year Of Work On #StopChildAbuse, #TraceAnObject


According to our records, Europol posted a total of 60 new images between February 2019 and March 2020.

From those, a total of 50 have been removed from their platform and were likely identified. 

We worked on approximately 25 cases and identified 12 places and objects. The rest resulted in leads for other, past or ongoing, investigations. 

We identified pieces of clothing and bed sheets, sippy cups and paint containers. Important investigation notes and visual reconstruction of unidentified items such as corporate merchandise, pillow cases, t-shirts, calendars, chairs, etc., were shared on social media to assist the public in the identification process.

In our reports, we investigated images linked to the production of Child Sexual Abuse Material (CSAM) in Ukraine as well as sex tourism in Madagascar and Cambodia. Two more images were tracked down to a series of meeting rooms and a food court in Jiangmen, China. With the help of the public, more details were identified from images geolocated to Dmitrov and St. Petersburg. Now we have disclosed details from cases in Mexico, Panama, and Russia. 

The main objective at the core of our enterprise has been to increase the chances for any one child to be rescued. 

Bellingcat members have devoted more than 2,500 volunteer hours to the campaign.

Looking for clues, we checked more than 2 million images on the web and surveyed the equivalent to 70,000 square kilometers on Google Earth. Approximately 1,000 documents were researched as well.

Digital enhancement and reconstruction of images have been essential in assisting visual analysis. Site sketching, detailed 3D modelling, and building shadow simulation have provided key information to geolocate (determine the place of) and chronolocate (determine the time of) several cases. 

Links with different communities via talks and workshops, as well as active participation in other channels, have also contributed to the investigations with the help of a growing network of supporters.

With our article “Europol’s Child Abuse Image Geolocated In Ukraine: A Forgotten Story Hidden Behind A Landscape”, we have been nominated to the European Press Prize 2020 in the category of Innovation.

We thank all members of the public for their help and continuous feedback. Also many thanks to Europol for their positive comments on Twitter and during our launch event in the Hague.

We must also note the rest of the research team  — Daniel Romein, Timmi Allen, and “Bo” — as well as all the Bellingcat contributors brainstorming in our channels for this good cause.

Figure 12. A summary of our work on the StopChildAbuse – TraceAnObject campaign during 2019 – 2020



Creating Impact: Why Should We All Participate?


Key facts:

We know the fight against online abuse is much more complex than just identifying a batch of past Child Abuse Material (CSAM). 

The problem is an emergency that needs scaled action from all stakeholders: governments, law enforcement agencies, technology companies, the scientific community, NGOs, and members of the public. As long as the contributions are part of an organized and synchronized effort, as opposed to done in isolation, they will all add value to tackle the problem.

We base our work on the impact it can have — not just directly on the campaign, but also at the level of a faster and more efficient identification of information, leading to the rescue of victims as well as in the elimination and prevention of CSAM. 

Growing The Network

The success of this crowdsourcing campaign relies largely on spotting pieces of local knowledge in every corner of the world by everyday citizens and OSINT practitioners.

The larger the number of people aware and engaged with the campaign, the larger the chances for objects and places to be identified. 

Our last 4 #StopChildAbuse reports have been visited a total of 100,000 times since they went live in 2019. Investigation details have been shared to create awareness and to contribute with the OSINT methods applicable to identify future cases.

By sharing notes and brainstorming on different channels, we have done contributions in emerging communities that are growing extraordinarily. An example of this is the subreddit r/TraceAnObject

This independent community, where we also participate, was created in September 2019 as a space to create leads, brainstorm, and search for objects posted by Europol. The page currently has 48K members and has had between 25–200K unique visits in the weeks after every batch of images has been released. Each object receives 100 comments on average; this, in many cases, results in excellent leads for Europol. 

In our workshops, we discuss OSINT techniques applied to StopChildAbuse investigations. Many of the attendees now follow and contribute to the campaign. 

We have been also working with other networks to spread the word. For example, we will speak at the 2020 National Child Protection Task Force Conference to help with providing access to investigative expertise in a joined mission to protect children. 

We hope more members of the community, OSINT practitioners, journalists, businesses, and software developers keep joining up to contribute to the campaign, as well as any other similar initiatives from local and international law enforcement agencies.

Rescuing Victims

According to the last official update, ten victims have been rescued thanks to all the contributions people have sent in this crowdsourcing campaign. These children may never have been rescued without the help of members of the public. The rescue of even one child makes the massive collective effort more than worthwhile.

Faster Identification And Better Workflow Efficiency

Some images published by Europol might not directly lead to a victim’s identification and/or rescue or else to a perpetrator’s prosecution. However, identifying an item will eliminate investigative trails and investigators will be able to spend more time and resources on other leads with a higher potential for success. 

Europol is connected to the Interpol’s International Child Sexual Exploitation (ICSE) database. Here, investigators are able to compare images and make connections between victims, abusers, and places featured in other images in the database.

Every image identified in the campaign could also be linked to another unknown series of images. So, while the total number of material identified could be potentially higher, the victim identification process could be faster too.

Figure 13. Interpol’s International Child Sexual Exploitation (ICSE) May 2019


Eliminating And Preventing CSAM Via Hash Values And Artificial Intelligence 

Undetected online CSAM means the original recording of the act of abuse will keep circulating on the internet or dark web. Every time a person sees that image, the victim is in effect abused again. This is called revictimization. 

There are different technologies which assist stakeholders in the fight to eliminate and prevent illegal images and videos online. 

Current image analytics technology creates a unique digital footprint for abuse images via a method called hashing

ICCAM is a tool used by INHOPE hotlines with the aim to remove CSAM from the internet across different jurisdictions. It uses URL crawling and hash value comparison against INTERPOL’s baseline. If there is a CSAM match, hotlines alert the competent law enforcement agency and internet servers to remove the material.

Helping Europol identify abuse images means that they are then able to upload them to INTERPOL’s ICSE database. Those classified as baseline will facilitate the whole CSAM elimination process via hotlines’ hash value comparison while helping to reduce revictimization.

New technologies are emerging to automate more tasks and improve detection. AI image classifiers scan images for nudity, age, and body motion to determine whether the content is CSAM or not. The algorithms behind this technology are trained by CSAM databases.

Deep learning techniques, such as Scene Information, help detect objects and landmarks to locate the place of origin of an image — but these still need more development.

Similarly to how users identify people, places and images on social media, people are helping Europol to add “tags” to objects on CSAM files to then transfer them into a more organised database.

Without discussing the barriers in resources, legislation and technology, it should be noted that  a larger and more detailed ICSE could be used to train or improve AI technology to detect and prevent dissemination of CSAM.

Thinking of the future, could thousands of tips that the public sends in across different platforms could be used to assist algorithms in making decisions when identifying potential recurring objects and locations in new, pre-classified CSAM? This would help to link and prioritise cases more effectively and identify victims faster. 

Independently of the use, the question here is how the Stop Child Abuse — Trace An Object campaign could be scaled up to generate appropriate data faster in a way that it could be used by the authorities with the minimum amount of resources needed, with low risk for the victims and the  public, and with a means of preventing vigilante justice.



Our Recommendations For Europol

Depending on the resources available, and the strategy Europol want to follow for the next steps of the campaign, we would like offer some recommendations based on our experience investigating the cases, and on feedback from the public:

Digital Enhancement Of Images

We need to consider that it might not be easy for everybody to quickly recognise objects and clues in the items listed on the website. 

Whenever possible, and without eliminating the original low resolution file; adding digitally enhanced versions of the same object in different sizes and angles might increase the chances of everyday citizens recognising objects; including those they may have been familiar with years ago. 

For example, participants could zoom in with their mobile phones to see details on a T-shirt logo — but this alone might not be enough to make it clear and visible. Offering extra views with AI-enlarged close-ups of the item’s features will be extremely helpful in assisting object memory.

Perhaps experts in the field of visual memory would be able to develop a study on what is the best way to present objects on your website. Although this might need an upgrade of the web platform, the number of relevant leads could be increased significantly. 

Description With Context

When the material and legal framework allow it, adding as many observations as possible from the scene will be very beneficial. The information could be in the form of keywords, titles, tags, places, etc., but they should be presented with high accuracy too.

Example1: “Do you recognize this sports arena?” vs. “Do you recognize this sports arena likely located in Central or South America?”  — the second option definitely offered us extra key information that allowed a faster identification of the place.

Example 2: “This is a child’s body warmer or similar. Can you recognise the brand or know where you can buy it?” — the item in this particular case turned out to be a swimsuit instead. Inaccurate definitions could mislead participants and delay the identification process.

Example 3: The recent case geolocated in Cambodia involved 3 images. However, the images were presented separately, without any reference to link them. Grouping objects and adding references will be highly beneficial.

Engagement & Feedback 

Julia Muraszkiewicz outlined some of the challenges that exist for law enforcement agencies when relying on community engagement in the form of crowdsourcing, specifically when it comes to Stop Child Abuse — Trace An Object. 

It will be interesting to analyse data and understand the demographics of the people supporting the campaign. We suspect the initiatives are being followed closely by OSINT practitioners and perhaps more efforts should be made to engage more everyday citizens around the world, so they can contribute with local knowledge. The interaction between both groups is highly effective. See case #C8032019 for an example of this productive collaboration.

Focusing on sustaining the campaign, we particularly believe that a better and continuous feedback from Europol to the public will ensure better engagement.

More frequent reports similar to the press release from February 2018 should be published.

At least once a year, people should be informed about other indirect results of the campaign and progress relative to other goals using more performance indicators. It would be also interesting to know what sort of partnerships or work is being done with charities, NGOs, and other institutions in order to reach and engage more people. 

Regular videos and podcasts, like the BBC’s stories, for example, would be powerful instruments for engagement too.

Mobile interactive stations and apps like the Crowdsourcing Intelligence Agency shown at international exhibitions, conferences and events could give different audiences the chance to identify objects and understand the problem in more depth. This is a great opportunity to partner up with relevant international charities and organisations.

According to the 2019 year report from INHOPE, they have partnerships with key stakeholders to cooperate in the elimination and detection of online CSAM — these include Europol, Interpol, and ECPAT. All three should work closely to help disseminate the relevant #TraceAnObject information via their online channels. We think there is scope to engage more members of the public in numerous regions where they have presence via online channels (inc. other languages).

Example of the number of Tweets related to the campaign shared by these organisations in the last 3 years:

Europol: over 50 posts 

ECPAT International: 5 posts

INHOPE International: 5 posts

Interpol_HQ and Interpol_Cyber: 0 posts

Volunteers spend a considerable amount of time investigating some of the cases. Sometimes many of these have already been identified but are not updated or removed from the platform for a very long time. While the reasons for this approach, meant to conceal the status of the investigation, are totally understandable, it can negatively impact the engagement of participants as they feel their time has been somehow wasted.

Perhaps, displaying a live counter (e.g. number of leads vs days online) or a colour scale on each item, could give participants an indication where more help might be needed without revealing the status of the investigation.

Different communities have also communicated that their members are keen to do more, but sometimes feel that the time between new batches of images is too long. After people do as much as they can, they find no other way to help, and interest drops. Some might then forget to come back and check for new items. 

More frequent batches of images could be beneficial. Also, frequent reminders of individual objects via Twitter, like it was done in the past, could help to keep momentum going between batches. A subscribe button on your webpage could give people the possibility to opt in to receive alerts when new items are posted.

Organising “hackathons” or task force events adapted for people to identify objects and places could help in engaging more participants, especially those from the OSINT community.



A Final Note From The Author

I decided to support @Europol’s Stop Child Abuse — Trace An Object a year ago, after watching a BBC World report called Tracing child abusers: Where was this picture taken?

I had no OSINT background at the time, but what I did have were visual analysis and research skills and determination to help the campaign. After some weeks looking for clues, trying to geolocate a rather desolated landscape featured on Image G5, I joined Bellingcat.

Now, after dedicating approximately 1.500 volunteering hours of my time to this cause, I feel proud of the impact we have all created as a community working together. It has been an amazing experience to take part in this wonderful cooperation between OSINters, researchers, Twitter and Reddit users with the sole only objective of helping victims of abuse.

At Bellingcat, we will continue supporting this cause, and are continuously exploring new ideas on how to help more as the campaign grows.

For everyday citizens around the world: Every 3 months or so when Europol releases images, please have a look and see if you are familiar with some of the objects! Five minutes, that’s all it takes.

Fellow OSINTers and researchers: This is a great way to test your skills at any level. Do you have the time and perseverance needed? You can find out!

Everybody can participate and send their tips using Europol’s online form. If you want to help with the research, please start brainstorming and share your ideas on r/TraceAnObject or Twitter using the new hashtag reference given for each object published by Europol. Check this thread to understand the process.

Last but not least, I would like to individually thank the rest of the research team for our great cooperation, and the excellent results achieved with our investigations:

Thank you to Daniel Romein: Fantastic research and eye for detail and precision. Great support and guide at any time.

Thank you to Timmi Allen: The magic maker in visual enhancements. The keystone in the forensic process.

And a thank you to Bo: More than 40 objects identified, an amazing effort.