Thirty-two workers were rescued from a flooded coal mine in China on Tuesday after being trapped for nearly a day, while the boss was being probed for running an illegal operation, state media reported.

The workers were lifted out of the flooded shaft in Henan province shortly after 6:00 am (2200 GMT Monday), almost 24 hours after the accident occurred, and all were in stable condition in hospital, Xinhua news agency reported.

However, two of their colleagues were found dead, according to the agency.

Xinhua said an earlier report it had published stating 33 workers were rescued had been wrong.

The accident at the Gaomendong Coal Mine near Pingdingshan city happened at about 7:20 am on Monday.

Forty-two miners were at work at the time of the flooding and eight managed to escape shortly afterwards, Xinhua said.

However, it was two hours before the mine owner reported the accident, and he had also not passed on earlier warnings from miners that water had been seeping into the shaft, Xinhua said.

The owner, Lou Gaofeng, had been detained, the agency said, adding the mine had been operating illegally, even though its production licence was valid until November 2009.

"The mine was undergoing a technical renovation... and had yet to be approved for resuming production," said Wang Dexue, deputy head of the state administration of work safety.

Also on the list of security lapses was the finding that too many workers had been in the mine at the time of the flooding.

"The mine allows a maximum of 28 miners. But 42 people were working underground when the accident happened," said Li Hanwei, vice director of the rescue operations.

It was the third coal mine accident in less than three weeks in Henan, with a total of five miners dying in the two previous accidents, Xinhua said.

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

Nearly 3,800 people died in Chinese coal mines last year, according to official figures. However, independent monitors say the real figure is likely much higher as many accidents are covered up.