The Malian army and foreign fighters executed at least 500 people during an anti-jihadist operation in Mali in March 2022, according to a much-awaited UN report released on Friday.
The figures by the UN High Commissioner for Human Rights (OHCHR) amount to the worst atrocity the Sahel country has experienced since a jihadist insurgency flared in 2012.
It is also the most damning document yet against Mali's armed forces and their foreign allies.
Their nationality is not explicitly identified in the report, although Mali has brought in Russians that western countries and others say are Wagner mercenaries.
Describing events that unfolded in the central town of Moura between March 27-31 2022, the OHCHR said it had "reasonable grounds to believe that at least 500 people were killed in violation of norms, standards, rules and/or principles of international law".
The victims were "executed by the FAMa (Malian Armed Forces) and foreign military personnel" who had complete control over the area, it said.
- 'Grave concern' -
The United States, Britain and Canada, in a joint statement sent from their Mali embassies, expressed "grave concern over the report's conclusions implicating elements of the Malian Armed Forces and Russian-backed Wagner Group ('foreign military personnel') in documented crimes including sexual violence, torture, and extrajudicial killings".
They called on Mali's transition government to hold an independent investigation and to release the findings and "hold accountable those responsible for these appalling acts of violence".
The UN report was published after a lengthy investigation by the human rights division of the UN peacekeeping mission in Mali, MINUSMA.
Around 20 women and seven children were among those killed, while evidence suggests 58 women and girls were victims of rape and other forms of sexual violence, the report said.
Acts of torture were carried out on people who had been detained, it added.
UN High Commissioner for Human Rights Volker Turk called the findings "extremely disturbing".
"Summary executions, rape and torture during armed conflict amount to war crimes and could, depending on the circumstances, amount to crimes against humanity," he said in a statement.
There was no reaction from Mali's ruling junta by mid-afternoon on Friday.
- Russia question -
Mali is ruled by a military junta which in 2020 toppled the country's elected president amid protests over the failure to roll back the jihadists.
Since then, the junta has brought in Russian operatives and warplanes to help its beleaguered armed forces, having severed ties with France, the country's traditional ally.
It says the Russians are providing military training and denies accusations that they are Wagner mercenaries.
The UN report does not explicitly identify the foreign fighters, and the OHCHR, in response to reporters' questions on Friday, said it was unable to identify their nationality.
The report cites Malian official statements on Russian military "instructors", as well as comments attributed to Russian Foreign Minister Sergei Lavrov on Wagner's presence in Mali.
- Bloodbath -
Moura, in the Mopti region of central Mali, has for years been known as a stronghold of the Katiba Macina, a group affiliated with the Al-Qaeda-linked Support Group for Islam and Muslims (GSIM).
The report details the arrival of Malian soldiers and their allies, supported by five helicopters, in the late morning on March 27, 2022.
A livestock fair had that day attracted thousands of civilians there to buy supplies ahead of Ramadan.
About 30 Katiba Macina members were mingling with the fairgoers and civilians that day, the report said.
A helicopter reportedly opened fire "indiscriminately" in the direction of the market, and the jihadists returned fire.
Around 30 people, including a dozen jihadists, were killed.
The Malian army took control of the area within a few hours and arrested around 3,000 people, rounding them up in four locations, according to the report.
Malian soldiers and their allies "allegedly selected several hundred people who were summarily executed over at least four days," the report said.
The men executed were allegedly chosen on the basis of signs such as having long beards.
The victims were reportedly buried in mass graves.
- MINUSMA tensions -
On April 1, 2022, the junta described the events in Moura as a successful anti-jihadist operation that had put 203 "terrorists" out of action.
Five days later, Human Rights Watch (HRW) said 300 civilian men, some of them suspected jihadists, had been summarily killed. White foreigners, identified by several sources as Russian, had taken part, it added.
A Malian military court prosecutor announced an investigation in April 2022.
The new report comes as the UN is preparing to consider whether to renew the mandate of the 10-year-old MINUSMA mission.
Mali's authorities frequently attack MINUSMA'S activities in the field of human rights, expelling the head of its rights division earlier this year.
Friday's report is based on a seven-month investigation between March and October 2022 and on 157 individual interviews and 11 group interviews.
The junta persistently denied the investigators access to Moura, apart from one initial flyover.