At least 35 people were killed and 44 others were trapped after a gas explosion at a coal mine in central China early Tuesday, the government's work safety watchdog announced.

A total of 93 people were working in the mine in Pingdingshan city in Henan province when the blast took place in the early hours, the State Administration of Work Safety announced on its website. Fourteen were able to escape, it said.

A spokesman for the work safety watchdog surnamed Cao told AFP that rescue efforts were ongoing, adding that an agency official had been dispatched to the scene to oversee the operation involving dozens of personnel.

Ventilation was restored in most of the mine shafts before noon, the official Xinhua news agency reported, quoting Zhang Jufeng, an official with the city's coal mine bureau.

The agency, quoting a spokesman for the city's Communist Party committee, said the Xinhua No. 4 pit was undergoing renovations and had not yet been authorised by the city government to resume operations.

The explosion came just a few days after Vice Premier Zhang Dejiang called on authorities to improve safety in the country's coal mines -- in particular to prevent gas blast accidents, according to remarks published by Xinhua.

China has a dismal work safety record, with thousands of people dying every year in mines, factories and on construction sites.

Its coal mines are among the most dangerous in the world, with safety standards often ignored in the quest for profits and the drive to meet surging demand for coal -- the source of about 70 percent of China's energy.

Official figures show that more than 3,200 workers died in collieries last year, but independent labour groups say the actual figure could be much higher, as many accidents are covered up in order to avoid costly mine shutdowns.

Luo Lin, the chief of the State Administration of Work Safety, said Saturday that officials would shut down about 1,000 small coal mines this year, in an attempt to improve management and safety.

Luo said seven major coal mine accidents in China in August all occurred at small facilities.

More than 12,000 small coal mines whose annual output was less than 300,00 tonnes have been shut down nationwide since 2005, according to Xinhua.

The mine in Pingdingshan had an annual output of 150,000 tonnes, the agency said.

China's raw coal production rose 8.9 percent year-on-year in the first seven months of 2009 to 1.61 billion tonnes, the agency reported.

Due to the country's heavy use of coal to power its fast-paced economic growth, it has become one of the two biggest emitters of greenhouse gases alongside the United States.