Several residents, and an association promoting the Fulani ethnic group, have said that on January 3 a helicopter attacked the village of Bounti during a wedding party, killing about 20 people.

Separately, the French military said a fighter jet had struck a jihadist group at a location north of the village, killing several dozen combatants.

The French military rejected any mistake, denying that a wedding party had been hit or that it had struck women or children. It added that the jihadists had been monitored for several days and no helicopter was used in the strike against them.

The 13,000-strong UN peacekeeping force in Mali, known as MINUSMA, launched an investigation in the aftermath of the strike.

On Thursday, it said in a statement that its investigators had visited Bounti on Monday.

Fact-finders interviewed witnesses and were able to "verify some information," according to the statement, which did not offer further details.

MINUSMA will release its findings in a forthcoming report, the statement said.

Mali has struggled to quell a jihadist insurgency that first emerged in 2012, before spreading to the centre of the country and neighbouring Burkina Faso and Niger.

France intervened in the country to beat back the jihadists in 2013, and now has some 5,100 soldiers deployed across the semi-arid Sahel region.

The French military conducted the airstrike as part of "Operation Eclipse" -- an anti-jihadist push that took place between January 2 and 20, mainly in central Mali.

Mali's army, which also took part, said that about 100 jihadists were killed during the operation.

Human Rights Watch, International Federation for Human Rights and the Malian Association of Human Rights have all called for independent investigations into the airstrike.