At least seven workers have been killed when a colliery roof caved in China's northeast Heilongjiang province.
The incident took place on July 5 at Xingcheng Coal Mine but the owner of the mine hid the accident fearing consequences, state-run Xinhua news agency reported.
A probe was launched into the incident after several people provided clues of the accident to city authorities in Hegang city, officials said.
The owner delibrately covered up the incident fearing the consequences, they said, adding that seven workers were killed and one got seriously injured in the incident.
