Four miners were still trapped in a flooded coal mine in Shanxi, a major coal-producing province in north China, local authorities said Saturday.

The accident occurred at about 4:30 PM Friday in a coal pit run by the Lingshi Coal Mine Co., Ltd. in Lingshi County when six miners were working underground, the county government said. Two managed to escape.

More than 60 rescue workers have been pumping out the water and trying to reach the trapped workers.

Investigation into the cause of the flooding was under way.

The ill-fated mine is undergoing output upgrading since August of last year to raise its annual production capacity to 900,000 tonnes.

(Xinhua News Agency January 16, 2009)