At least 15 drivers were killed in an attack by suspected militants on a fuel tanker convoy in western Mali last week, local and security sources said on Monday.

The attack took place on Thursday along a route linking the Senegalese border to the Malian city of Kayes, sources told Agence France-Presse.

A security source, speaking on condition of anonymity, said fighters from Jama’at Nusrat al-Islam wal-Muslimin (JNIM), an al Qaeda-linked group, intercepted the convoy and executed the drivers at close range after blindfolding them.

A local radio employee, citing a local official, said 15 bodies were found at the scene alongside burned-out fuel tankers.

Since September, JNIM has stepped up attacks across Mali, imposing blockades on several towns and repeatedly targeting supply convoys. Local sources said this was the first time truck drivers had been directly executed in such an attack, although drivers have been killed in previous assaults.