Exclusive: The first proof of the use of chemical weapons in Sudan’s civil war

On September 5 and 13, 2024, barrels containing chlorine gas were dropped from the air near a refinery north of Sudan's capital, Khartoum.

Using open-source investigation techniques (OSINT), the FRANCE 24 Observers team verified videos and photos documenting the two incidents. After reviewing images of the attacks, five experts confirmed they were consistent with aerial drops of chlorine barrels. 

At the time, the army was trying to recapture the refinery from the Rapid Support Forces (RSF) militia, their opponents in the ongoing civil war. The barrels were dropped from the sky, and the Sudanese army is the only force in the country with the aerial military capacity to carry out such a drop.

Read moreVideos show the Sudanese army's use of chlorine gas as a weapon

Chlorine imported for water purification

Thanks to exclusive documents, the Observers team was able to trace how these barrels of chlorine used as chemical weapons were brought to Sudan.

Our investigation shows that the chlorine was exported to Sudan by Chemtrade International Corporation, an Indian company. They said it was intended exclusively for water treatment purposes, a common civilian use.

We also found that the chlorine gas was imported by Ports Engineering Company, a Sudanese company. Its website states that the company specialises in public works and water treatment, an apparent reference to the production of potable water.

However, there is no indication that the chlorine barrels were imported for use at Sudanese water-treatment centres. 

Thanks to commercial data provided by the American NGO C4ADS, we found that Ports Engineering is implicated in the importation of military equipment, and has commercial links with an Emirati company that supplies uniforms and shoes to the Sudanese intelligence service.

Commercial data shows that the Indian company Chemtrade has shipped at least 125 chlorine gas cylinders to Sudan since the start of the civil war. Was chlorine imported to be used as a weapon? Or for purifying drinking water? Without any response from the company or the Sudanese army, it is impossible to determine. 

Read moreHow did chlorine imported to Sudan for water purification end up being used as a poison gas?

Nearly 17.3 million people lack access to safe drinking water in Sudan, making it a critical issue across the country. One of the barrels dropped in September 2024 would have been enough to cover the basic needs for three months of the million displaced persons who have returned to Khartoum since the army recaptured it on March 26, 2025.