BEIJING, Feb 15: A gas explosion in a coal mine in China's north eastern rust-belt province of Liaoning killed at least 203 workers in the worst recorded disaster in 63 years.

The explosion, on Monday afternoon at the mine in Fuxin city, injured 28 miners and 13 were still trapped. A rescue team of more than 180 people was working to free trapped workers.

The blast occurred 242 metres below ground at the Sunjiawan colliery of the state-owned Fuxin Coal Industry Group. Dozens of miners wearing hard hats, dusty uniforms and long faces gathered at the entrance to the mine shaft, waiting for news of missing colleagues.

"We have never seen such a big accident before," said an official at Fuxin's Coal Mine Safety Supervision Bureau. "The rescue operations are still going on and the coal mine is still verifying the conditions of workers," he said. "We still don't know the real cause of the accident because the formal investigation has yet to start."

Workers reported feeling a sudden, strong tremor shake the mine 10 minutes before the blast, Xinhua said, quoting a senior official at Fuxin Coal. Moments later, gas detectors lost their signals and one of the mine's main pits filled with smoke, Xinhua said.

President Hu Jintao and Premier Wen Jiabao called for officials to take "all possible measures" to rescue trapped workers. China was the site of the world's worst recorded mining disaster when 1,572 people were killed on April 26, 1942, in an explosion at the Honkeiko mine.

INJURED WORKERS: The 28 injured workers - suffering burns, fractures or chemical poisoning - were taken to hospital. One was hurt seriously and in a coma. "Most of them are slightly injured, but one of them is suffering from external head trauma," a hospital official said.

About 30 family members of the victims were hospitalized because of deep grief, Xinhua said. Liaoning Governor Zhang Wenyue was supervising the rescue operation at the mine, which employed 3,100 workers and was designed to produce up to 1.5 million tons of coal a year.

Output at the mine used to be low, Xinhua said, before it was acquired three years ago by Fuxin Coal, one of China's biggest coal producers. It was classified as a "high-gas" mine, with high levels of potentially combustible gases.

A Fuxin resident said many of her neighbours worked for the coal mine. "We are of course shocked and feel very sad about it because people are still enjoying the Lunar New Year," she said.

Residents have long depended on coal, oil and metal mining in the area for their livelihood, but many have lost their jobs because of dwindling reserves. Four years ago, leaders ordered Fuxin to diversify its economy into a modern farming community to create more jobs. But with high unemployment, many miners cling to their dangerous jobs. A coal mine blast in Fuxin last year killed four people.

NATIONWIDE CHECK: A spokesman for the State Administration of Work Safety told state television it would carry out a nation wide check on high-gas coal mines. -Reuters