Rescuers said Thursday they had heard cries for help from a blocked mine shaft in which five miners had been trapped since noon on Wednesday in central China.

Rescue efforts at the Manaoshan Mine in Chenzhou City, Hunan Province, would continue so long as the trapped miners had a chance of survival, said a work safety official.

More than 100 people were trying to reopen the tunnel, which was blocked by a mud-rock flow, trapping five miners 10 meters underground.

"Utmost efforts will be made so long as there is a sliver of hope," said Zhang Riqing, vice director of the Chenzhou Administration of Work Safety.

The blocked area was 2,000 meters from entry of the shaft. Due to limited space, rescuers were taking turns to dig in teams of four. Their work was also hampered by silt in the tunnel.

The Manaoshan Mine produces a mix of iron, manganese and other ores.

(Xinhua News Agency December 17, 2009)