CHONGQING • Rescuers were working around the clock yesterday, searching for 20 miners who had remained trapped in a colliery in China for nearly 24 hours following a gas explosion.

Altogether, 33 miners were stranded in a pit at Jinshangou coal mine in Yongchuan district in the south-west municipality of Chongqing after the explosion went off at 11.33am on Monday.

As of midnight the same day, rescuers had retrieved 13 bodies, but the remaining 20 miners were still unaccounted for, said Chongqing's deputy mayor Mu Huaping at a press briefing yesterday.

He corrected casualty reports provided by the local coal-mine safety authorities on Monday, which said 15 miners had been confirmed dead. "We are still working all out to search for the 20 missing miners and will exert our utmost as long as there's still a ray of hope," he said.

More than 400 rescuers were working overnight. They needed to dig through the underground passageways, some of which had been blocked by ruins from collapsed tunnels, carefully avoiding secondary disasters.

Ms Liu Fuxiu, a winch operator with the mine, was working 40m from the entrance to the pit. She was swept away by strong shockwaves following the explosion and was injured on the face and back.

Altogether, 35 workers were in the pit when the accident happened. Two of them managed to escape unhurt.

XINHUA