Malian troops and suspected Russian fighters allegedly executed around 300 civilian men over five days during a military operation in a central Mali town, Human Rights Watch (HRW) said in a report on Tuesday, which the country's army refuted.
The killings took place between March 27 and 31 in Moura, a rural town of around 10,000 inhabitants in the Mopti region, a hotspot of extremist activity that has intensified and spread to neighbouring countries in the Sahel region.
"The incident is the worst single atrocity reported in Mali's decade-long armed conflict," HRW said.
The reported executions sparked condemnation from the United States, the European Union, France and Germany, who have all called on the Malian government to allow for an independent investigation.
The West African country's army on Tuesday denied the allegations and said it had conducted a professional, well-executed operation in Moura to target Islamist militants. It previously said it had killed more than 200 after learning that they would be meeting there.
"The total control of the locality allowed for searching, identifying, and sorting out terrorists disguised and concealed among the civilian population," the army said in a statement.
After a gunfight, it said the army used a helicopter to pursue and "neutralise" militants who were trying to flee. Suspects in the town were then arrested and flown out to face trial, it said.
Witnesses told HRW a different story.
Nineteen witnesses told the rights group that Malian and Russian-speaking soldiers arrived by helicopter and exchanged two rounds of gunfire with Islamist fighters, during which rebels, soldiers and a few civilians were killed.
The troops then deployed through the town, summarily executed several men then gathered hundreds of other unarmed people from their homes and took them to the bank of a nearby river, the witnesses told HRW.
Many were traders from surrounding villages who came to attend the town's weekly livestock market. Some of these groups were infiltrated by militants, the witnesses told HRW.
The men were held for five days under the sun and arbitrarily selected for execution by gunfire during the night. Bodies were piled into three mass graves, HRW said.
The operation allegedly involved over 100 Russian-speaking men, according to multiple security sources who spoke to HRW.
Several witnesses also described white soldiers speaking an unfamiliar foreign language they believed to be Russian.
One trader said he was drinking tea with his two brothers while waiting for the market to start when he heard shooting.
"Seven Russians approached, gesturing for us to get up. There were no Malian soldiers with them. They searched us and the house, then took us east of the village, near the river, where we found another 100 men," he told HRW.
"Another group of Russians pointed at my brothers and another man. I thought they were going for interrogation. They took them several metres away and executed them, point blank," he said.
Reuters was unable to independently confirm the witnesses' accounts cited by HRW.
Mali's transitional government, which took power in a 2020 military coup, is battling the insurgency with the help of private military contractors belonging to Russia's Wagner Group.
Both Mali and Russia have previously said they are not mercenaries but trainers helping local troops with equipment bought from Russia.
France, Mali's former colonizer, has had thousands of troops battling militants in the country for nearly a decade but said earlier this year it was pulling out after relations deteriorated, in part due to the arrival of the Russian fighters. A French-led mission of 14 mainly European nations with 600-900 soldiers in Mali is also winding up.
(Reporting by Sofia Christensen; Additional reporting by Paul Lorgerie in Bamako; Writing by Sofia Christensen and Nellie Peyton; Editing by Bate Felix and Nick Macfie)
