ZHONGNING, Ningxia, June 27 (Xinhua) -- The death toll in a coal mine explosion rose to five as three more miners died after treatment failed Saturday in northwest China's Ningxia Hui Autonomous Region, local authorities said.
The explosion happened at around 2:30 a.m. at Hongyuan Coal Mine at Shikong Town of Zhongning County. A total of 12 people were trapped underground, according to the county's committee of the Communist Party of China.
Seven injured were still in a critical condition and were being treated in hospitals. They were poisoned with carbon monoxide, said Wang Jun, head of the county's health bureau.
The township-owned coal mine has been ordered to suspend operation for a safety overhaul, when the accident happened, according to the regional coal mine safety supervision authorities.
An initial investigation showed that the explosion was triggered by burning explosives