Beijing - Several hundred people could be missing after mud and rock buried a market and other buildings in northern China's Shanxi province, killing at least 34 people, the government and state media said on Tuesday.

Initial state media reports said only that a warehouse at an iron mine was destroyed by the mud and rock flow early Monday, but the official Xinhua news agency on Tuesday said a market, an office block and several homes were also engulfed.

More than 1,100 police, firefighters and local residents, aided by mechanical diggers, continued to search through mud and rubble for survivors on Tuesday in a valley near Shanxi's Linfen city, the agency quoted rescue coordinator Ding Wenlu as saying.

The rescue efforts around the Tashan mine in Xiangfen county were hampered by "rough terrain, poor telecommunications and continuous rainfall," the agency said.

The State Administration of Work Safety said the confirmed casualty toll had reached 34 dead and 35 injured, four of them seriously, by Tuesday morning.

Torrential rain caused mud and rock to flow down a hillside and engulf the buildings.

The agency quoted witnesses as saying the mud flow "roared down the valley and washed away the market and the houses in a few minutes."

It said police detained the owner and eight others involved in running the mine, part of which was apparently illegally reopened.

The safety administration said the exact number of people trapped in the debris was still under investigation.

Xiangfen county has several iron ore mines which employ many migrant workers from Shanxi and other provinces, making it difficult for local officials to identify the victims of the mudslide, the agency said. (dpa)