Acute respiratory distress, unusual odours, coloured explosive blasts, long term health problems, and environmental degradation are among the indicators that a group of experts has identified as credible evidence to support witness accounts of exposure to toxic chemicals linked to military activity in Sudan between 2024 and 2025.
The findings are described in a 32-page investigation, seen by Euronews, into the use of chemical weapons in civil areas in Sudan amid the ongoing war that started in 2023.
The investigation was led by former senior officials of the Organisation for the Prohibition of Chemical Weapons (OPCW), two of whom served with the organisation when it was awarded the 2013 Nobel Peace Prize for its work to implement the global ban on chemical weapons.
The two former senior OPCW officials leading the team talked to Euronews, but requested that their names remain anonymous due to the sensitive nature of the content.
“Given that at least one State Party has sanctioned individuals in relation to the alleged use of chemical weapons, that there are new and increasing allegations of a hidden programme, and that there is strong witness testimony indicating that there was an incident in September 2024 that may have involved chlorine, the OPCW and it’s States Parties need to launch an investigation,” the two former senior officials told Euronews.
The report cites the testimony of eight Sudanese witnesses, corroborated by video, pictures, and other digital material produced by the alleged victims, which indicates that chemical weapons might have been used in the conflict.
Euronews reviewed the pictures contained in the report, but could not talk to the witnesses nor inspect their video footage or other digital evidence.
This is not the first time that evidence has been produced indicating the possible use of chemical weapons in Sudan. Both the New York Times and the Washington Post published investigations in early September drawing on evidence provided by Middle Eastern intelligence, including pictures of stockpiles and correspondence among Sudanese officials. It was the alleged use of chemical weapons that led the US government to impose sanctions on Sudan in April 2025.
But the investigation reviewed by Euronews adds both a human dimension and substantive grounds to the serious allegations, and is set to draw further attention.
The Sudanese government has denied any wrongdoing on multiple occasions.
The report
According to the report, the team of experts interviewed eight witnesses in the Kenyan capital, Nairobi. Together, they identified “a number of credible incidents involving unexplained illness following military activity”.
The group was composed of “individuals reporting direct exposure to alleged incidents, persons involved in emergency response activities, a healthcare professional who treated affected patients and individuals able to provide supporting documentary and digital material relevant to the investigation,” the report reads.
The strongest evidence were provided by two witnesses interviewed separately who were both present during an incident at the Al-Jili Oil Refinery near Khartoum in September 2024.
At the time, the area was under the control of the Rapid Support Forces, the leading group fighting against the Sudanese army that has been sanctioned by the EU and the US for serious human rights violations.
“Both witnesses described a military aircraft flying overhead immediately before the incident,” the report says, listing “barrel-shaped objects associated with the overflight; impacts that did not resemble conventional explosive attacks; unusual airborne emissions; unfamiliar odours; acute respiratory symptoms affecting approximately twenty workers; treatment provided at the refinery medical clinic; subsequent change to vegetation close to the impact area”.
It specified that the acute respiratory and ocular effects described by the two witnesses are consistent with exposure to an airborne irritant or hazardous chemical. However, the team of experts was not able to identify the substance.
The other testimonies report other incidents in different places with recurring patterns.
“Several witnesses described aerial attacks followed by the rapid onset of respiratory symptoms affecting those in the immediate vicinity,” the report reads, explaining that the common described symptoms included “coughing, difficulty breathing, eye irritation and, in some cases, gastrointestinal or dermatological effects”.
Similar to the witnesses at the oil refinery they also described “unusual odours, coloured airborne emissions and the apparent absence of the explosive effects normally associated with conventional aerial bombardment”.
The team of experts could not conclusively confirm that the incidents were caused by the use of chemical weapons due to gaps that need to be filled in the findings.
However, they found credible and consistent evidence suggesting this may be the case, and have called on the OPCW to consider this evidence and pursue further investigation stemming from their preliminary findings.
According to UN data from April 2026, some 14 million people have been displaced since the Sudanese war began in 2023.
The conflict has also triggered what is widely described as one of the world’s worst hunger crises, with nearly 19.5 million people facing acute food insecurity and famine conditions.
Euronews approached the Sudanese government for comment, but received no reply before publication.