Société Minière de Bisunzu (SMB) on Wednesday said three people were killed and a three others were injured in a grenade attack on its tin mine in eastern Democratic Republic of Congo on Tuesday night.
SMB's mine near Rubaya, North Kivu province, has seen an increase in violent clashes between local artisanal miners and mine police.
Earlier this month a United Nations experts report said tantalum-rich ore coltan produced on the SMB concession was being smuggled off the mine by diggers and sold elsewhere.