A strong 5.7 magnitude aftershock on Wednesday rocked a remote region of Balochistan province where an earthquake killed dozens and flattened hundreds of houses even as Pakistani troops raced to provide aid to victims.

The epicentre of Thursday’s 7.8 magnitude quake lay in southeast Iran but most of the deaths reported so far have been reported across the border in Balochistan, where hundreds of mud brick homes were destroyed in Mashkel town and surrounding villages.

The region was rocked this morning by a powerful aftershock that measured 5.7 on the Richter scale, the U.S. Geological Survey said.

Army and paramilitary troops began fanning out to the affected areas last night to provide medical treatment and relief to the hundreds of victims.

There were conflicting reports about the total number of deaths, with civilian and security officials saying between 31 and 40 people had died.

They said nearly 100 people were injured when houses and buildings collapsed.

The military’s media arm said five helicopters and over 300 personnel, including army and Frontier Corps troops, doctors, paramedical staff and engineers, were engaged providing relief to the victims.

Army helicopters had shifted 16 seriously injured people from Mashkel to the provincial capital of Quetta.

A medical centre had also been set up in Mashkel, the military said.

Footage on television showed rows of mud brick houses that had been flattened by the quake in Mashkel. Houses that were still standing had huge cracks in their walls.

Officials told the media that 90 per cent of the homes in Mashkel and surrounding villages had been affected by the quake.