Fifty-three rescuers sent in to recover five trapped coal miners at a colliery in southwest China had to be pulled to safety Thursday after they too became stuck underground, state media said.

The five miners remain trapped in the mine in Guizhou province and have now been underground for over 32 hours, the Xinhua news agency said, citing rescue headquarters. They became marooned when a tunnel collapsed on Wednesday.

Rescuers were dispatched to dig a tunnel at the Anlilai Coal Mine, in Puan county, to reach the miners when a second collapse hit on Thursday, trapping them too.

The 53 rescuers were pulled out unscathed about six hours later, the report said, adding an investigation was under way into the cause of both accidents.

The mine has an annual production capacity of 210,000 tonnes.

Accidents in China's mines occur frequently.

However, tighter safety standards appear to have been effective according to the latest official figures, which say 1,973 people died in coal mining accidents in 2011, down 19 percent on the previous year.

China is the world's biggest consumer of coal, relying on the fossil fuel for 70 percent of its growing energy needs.