At least 30 people were killed when a gold mine collapsed in northeastern Afghanistan on Sunday, officials said.

Another seven were injured in the incident in the Kohistan district of Badakhshan province, according to district governor Mohammad Rustam Raghi.

A police spokesman earlier said the cause of the accident, which occurred in heavy snowfall, was a landslide.

Officials said the villagers, who were mining for gold illegally, had dug a 60-meter deep shaft in a riverbed to search for gold.

About 50 miners were inside when the walls caved in. It is not currently clear why the shaft collapsed.

Defense ministry helicopters have been dispatched to deliver cash to the families of the victims and airlift the wounded to hospitals, according to a disaster management official.

Badakhshan, a remote, mountainous province, is prone to landslides, particularly in the colder months when heavy snow blankets the province.