Nine miners died Sunday night from carbon monoxide poisoning in a colliery in central China's Henan province, local authorities confirmed Monday.

Liu Xianghua, deputy director of the Coal Mining Bureau in Yiyang city, said rescuers had found bodies of three of the mines under the mine shaft, and helped bring out six others to hospital, where they failed emergency treatment.

An initial investigation has found safety staff with the mine which belongs to Dongsheng Mining Co Ltd detected excessive amounts of carbon monoxide in the mine at 8:00 pm Sunday, when two miners were working underground. The company sent seven others to check the situation, but lost the contact with them afterward.

The company started the rescue work at 9 pm.