Rescuers searching for miners trapped by a coal mine explosion in northeast China (search) found six more bodies early Wednesday, bringing the death toll in the country's worst mining disaster in decades to 209, the government said.

Six other miners were still missing following Monday's blast in the Sunjiawan coal mine (search) in Liaoning province, the official Xinhua News Agency reported. Dozens of rescuers had searched through the night in subfreezing temperatures.

The cause of the gas explosion, the worst mining disaster reported in the country since Communist rule began in 1949, was under investigation.

Workers reported feeling a sudden, strong tremor shake the mine 10 minutes before the blast, which occurred about 790 feet underground. Moments later, gas detectors lost their signals and one of the mine's main pits filled with smoke.

By early Wednesday, the area outside the mine was quiet. The entrance was cordoned off, but there was no sign outside of rescue activity.

A convoy of white hospital vans filled with men in hardhats was seen traveling from the mine to nearby Fuxin, a gritty, soot-covered city of 1 million where mining is the main industry.

The blast, three years after the government pledged to boost safety standards amid a surge in industrial accidents, prompted the government to announce yet another nationwide inspection of coal mines.

"Mining is just too dangerous, but it's a struggle to find work here," said Zhang Qiang, a Fuxin native who said he works at odd jobs to make ends meet.

Fuxin lies in China's northeastern rust belt — a region teeming with inefficient, antiquated state-owned industries.

State media reported that 28 injured lay in hospital beds suffering from carbon monoxide poisoning, burns and fractures.

In October 2002, the government created the country's first national safety laws and launched a nationwide effort to improve job safety with a network of workplace inspectors. But deadly accidents have continued to plague the country's coal mines and factories.

Last year more than 6,000 miners died in fires, floods and explosions — an average of about 16 per day.

The accidents have been an embarrassment to the new Chinese leadership that took power in 2003, and that has taken pains to portray itself as sympathetic to the concerns of common people, especially farmers and miners.

The area where Monday's accident occurred is in one of China's oldest coal mining regions. Many of its mines have already been depleted. To reach coal seams, miners tunnel far underground, where the risks from explosions due to methane gas are high.

Monday's disaster was the deadliest reported by the Chinese government since the 1949 communist revolution. However, until the late 1990s, when the government began regularly announcing statistics on mining deaths, many industrial accidents were never disclosed.

In 1942, China's northeast was the site of the world's deadliest coal mining disaster when an accident killed 1,549 miners in Japanese-occupied Manchuria during World War II.

Last year, China accounted for 80 percent of the word's coal mining deaths.