Mali's army announced on April 1 that it had killed 203 militants in Moura, in the centre of the Sahel nation, during an operation in late March.

However, that announcement followed widely shared social media reports of a civilian massacre in the area.

Human Rights Watch also said this week that Malian forces and foreign fighters killed 300 civilians in Moura in late March, in what it called "the worst single atrocity reported in Mali's decade-long armed conflict".

On Wednesday, independent UN human rights expert Alioune Tine urged an independent and impartial investigation into the events.

In a statement, he called on the Malian authorities to allow the UN peacekeeping mission in Mali, known as Minusma, to perform the investigation.

"The findings must be made public and the alleged perpetrators brought to justice," Tine added.

The rights expert joins the United States, European Union, the UN and the Malian human rights commission in calling for an investigation into the alleged massacre.

UN spokesman Stephane Dujarric told reporters on Wednesday that the United Nations had launched a probe, and was trying to send investigators to Moura as soon as possible.

Mali's army said in its April 1 statement that it had carried out a "systemic cleansing" of the Moura area, and that it was guided by respect for international law and human rights.

On Tuesday evening, as reports of a massacre mounted, Malian army chief of staff General Oumar Diarra warned in a statement against "unfounded allegations" that he said sought to tarnish the military's image.

He added that Malian forces "do not operate against the civilian population, we are aware that the success of our operations depends on the support of this population".

Swathes of Mali lie outside of government control due to a brutal jihadist conflict that first emerged in 2012, before spreading to neighbouring Burkina Faso and Niger.

Thousands of soldiers and civilians have been killed in the conflict, and hundreds of thousands have been forced to flee their homes.

Mali's under-equipped army has often been accused of committing abuses.

The country's ruling junta, which seized power in a military coup in 2020, routinely defends the rights record of the armed forces.