A magnetic bomb attached to a passenger minivan exploded in a heavily Shia area of the Afghan capital Kabul on Saturday, causing an unknown number of casualties, Taliban officials and local residents said.

A recent spate of such attacks has heaped more pressure on the Taliban rulers, who took power following the collapse of the western-backed government in August and are also grappling with economic crisis and potential famine.

One Taliban official, who declined to be named, said six people had been killed and at least seven wounded in the blast in the Dasht-e Barchi area of western Kabul.

There was no confirmation of casualty numbers and no immediate claim of responsibility. The area is heavily populated by ethnic Hazaras who have been the target of repeated attacks by IS militants. Two Taliban officials said Islamic State was also behind Saturday’s attack.