An accident at a colliery in central China has killed four miners and trapped 50, state media said on Friday, in the latest disaster to hit the accident-prone industry.
The rock burst -- a sudden rupture of the rock face common in the mining industry -- occurred at the pit in Henan province while 75 miners were working underground, though 14 managed to escape soon after, Xinhua news agency reported.
Seven others were later rescued alive and emergency workers were trying to get the others out, the China News Service added.
China's mines are the deadliest in the world, due to lax safety standards and a rush to feed demand from a robust economy.
In 2010, 2,433 people died in coal mine accidents in China, although this was an improvement on the toll of 2,631 a year earlier.
(Reporting by Ben Blanchard; Editing by Ron Popeski)