LANZHOU - Three people have been confirmed dead and another seven were missing after an avalanche occurred late Tuesday night in a remote part of northwest China's Gansu province, local government sources said Wednesday.

Hu Jianzhong, head of Heicigou Antimony Ore Prospecting Station in Subei county, said the avalanche engulfed the team's campsite. Ten people were believed to have been buried.

There were a total of 21 people at the campsite at the time of the avalanche, and 11 managed to escape. Rescuers have sent one severely injured survivor to hospital, Hu said.

Rescuers led by Xi Zhongping, Communist Party chief of Subei County, are still searching for survivors and double-checking the number of workers who may have stayed at the campsite.

Heicigou, situated over 4,300 meters above sea level, is located 180 km away from the county seat of Subei, which is a dense Mongolian ethnic area.

Since Monday, the area had been hit by heavy rainstorms rarely seen in local history, and the local observatory said precipitation exceeded 500 millimeters in the 23 hours prior to 3 pm Tuesday.

The prospecting team is owned by Subei Jinze Mining Co. Ltd.. The share-holding company has prospecting rights on a 1,600-square-km area in Subei.