A gas explosion ripped through a coal mine in eastern China, killing at least 63 miners and leaving 23 others missing 500 meters underground, local officials said yesterday.

　　The explosion struck the Luling Coal Mine in northern Anhui Province at 4:13 pm on Tuesday.

　　Rescuers recovered 63 bodies by early yesterday and have found no signs that the other miners are alive, said an official in the mine's administration office.

　　"The chances that the missing miners survived are very small," said the official, who refused to give his name to reporters.

　　The missing miners are some 500 meters below ground, said an official in the local police station.

　　"To be optimistic, they can survive three days if they have enough water," said the police officer.

　　Rescued were 28 of the 114 people working in the mine at the time of the blast.The province's Governor Wang Jinshan and Vice Governor Huang Haisong were at the scene to organize the rescue work. A special rescue team is carrying out the rescue work underground.

　　Authorities have closed all the coal mines in northern Anhui Province to inspect working conditions. Only those meeting proper safety standards could resume operations, officials said.

　　The cause of the blast was under investigation, the officials said.

　　Coal mines in China reported more than 5,000 fatalities last year in explosions, floods and cave-ins. Explosions are often blamed on a lack of ventilation to clear natural gas that seeps out of the coal bed.