A vast portion of an outdoor opencast mine in China's Inner Mongolia autonomous region collapsed on Wednesday, killing at least two persons and leaving 53 missing, local officials said.
The incident happened in Inner Mongolia autonomous region's Alshaa Left Banner and the authorities were at work to rescue those trapped inside.
A preliminary investigation showed that more than 50 people were trapped under the mine, the State-run China Daily reported, quoting the emergency management authority in the league.
Eight persons trapped were saved, among whom two showed an absence of vital signs and six were sent to a hospital, according to the publicity bureau.
The rescue operation is being carried out by eight teams consisting of 334 rescue workers, 129 rescue vehicles of various types, and nine safety production experts, the State-run Xinhua news agency reported.
Rescue personnel from nearby areas have also been dispatched to support the ongoing efforts to find the missing men, it said.