"Whole families of Fulani shepherds were killed in the bushes of Solenzo, in the Bema and Ban areas," the source told AFP on condition of anonymity, giving a toll of "several dozen deaths".

Primarily nomadic herders, the Fulani people are often stigmatised across the wider Sahel, accused of collaborating with the jihadists who stalk the region and providing the bulk of their recruits.

Since Wednesday, videos of dozens of bloodied bodies strewn across the ground, with no apparent sign of life and hands and feet bound, have spread across social media. Most of the victims appear to be women, children or elderly.

In one video men armed with assault rifles and blood-stained knives, wearing T-shirts appearing to mark them out as members of local self-defence groups, are seen straddling the corpses on the ground, hurling insults at them.

"No filming," a voice orders the person behind the camera, who immediately complies.

In another video, the same armed men drive a three-wheeled vehicle loaded with lifeless bodies towards an unknown destination.

- 'Military strategy' -

The local source said that the bloodshed followed an attack at the beginning of March in the area.

"They accused the Fulani people of having sheltered the terrorists who committed the attack. Locals asked the Fulani to leave the area to avoid reprisals," they added.

"While leaving Solenzo they were caught up with by soldiers from the 18th rapid intervention brigade and some volunteers. They were tortured and massacred," the source said.

A human rights group official, who verified the authenticity of the grim videos, told AFP "this sort of operation tallies with the strategy of the military in Burkina Faso, targeting Fulani civilians in retaliation".

In the past decade Burkina Faso has been caught up in a spiral of jihadist violence spilling over from neighbouring Mali and Niger, which has since spread far beyond the three countries' borders.

All three have experienced coups in recent years by military rulers who have pledged to turn the tables on the Islamist groups.

Since 2015 the unrest has killed more than 26,000 people, both civilians and soldiers, across Burkina Faso, according to conflict monitor ACLED.

That tally included more than 13,500 victims who have died following the September 2022 coup which brought the military to power.

Between January and July 2024 the Burkinabe army and its auxiliaries killed "at least a thousand civilians", according to Human Rights Watch.