At least 50 civilians were killed and hundreds arrested in central Mali in April during an operation by the army and "foreign" personnel, the UN's peacekeeping mission said Wednesday.

The incident happened on April 19 when Malian troops "accompanied by foreign military personnel" carried out a sweep in Hombori after one of their convoys was attacked by a roadside bomb, MINUSMA said.

"At least 50 civilians (including a woman and a child) were killed and more than 500 others arrested," it said in a quarterly report on violence and rights abuses.

The report did not specify who the foreign fighters were.

Mali's ruling junta, which has been in power since 2020, has brought in Russian operatives it describes as military trainers.

Western countries describe them as mercenaries from the pro-Kremlin Wagner group.

Their presence has been a key factor in France's decision to withdraw its troops from Mali -- a former colony that it has supported in a decade-long fight against a jihadist insurgency that has claimed thousands of lives and forced hundreds of thousands from their homes.

The last French soldier in Mali under the long-running Barkhane anti-jihadist mission left the country on August 15.

The MINUSMA report said 96 civilians were killed during operations by Malian security forces between April 1 and June 30, while seven disappeared and 19 were injured.

A report by experts to the UN, seen by AFP in early August, said "white-skinned soldiers" accompanied Malian soldiers at the scene of killings in March in the Segou region near the Mauritanian border, in which 33 civilians died.

In April, Human Rights Watch (HRW) said about 300 people, most of them ethnic Fulanis, were killed in Moura in central Mali in March by Malian forces "or associated foreign fighters" -- a veiled reference to suspected Russian operatives.

Mali's army says that it killed 203 militants at Moura.