Five people are missing after a rain-triggered mudslide in northwest China's Gansu Province Thursday.

The mudslide buried seven people in Tianshui City, which is an hour helicopter ride from the mudslide-devastated county of Zhouqu. Two of the buried were quickly rescued.

Separately, in another part of Gansu Province, some 250,000 residents of Chengxian County are facing the threat of floods after overnight downpours raised the water level of the Donghe River, according to the provincial flood control and drought relief headquarters.

The water level in the river also rose after 10 boats broke their moorings and blocked the passage of water under a bridge.

The heavy rains and floods had cut power supplies in parts of Chengxian County and neighboring Huixian County.

Floodwaters had rushed into Huangzhu Township in Chengxian County, but it was not known whether anyone had been hurt or killed, said a statement from the provincial government.

In Huixian County, floods had damaged some homes and bridges, said the statement.

The rains also had left one dead and three others injured in Lixian County of Gansu after collapsing a wall, it said.

Floods have also submerged the road linking Tianshui and Chengxian. Emergency workers are rushing to the site to reopen the road.

Vice governor of Gansu Shi Jun is overseeing the disaster relief work in Chengxian.