Nanning (China), Oct 10 (Xinhua) Seven coalmine workers died and an equal number sustained injuries in a mine gas blast Friday morning in south China’s Guangxi Zhuang region, an official of the works safety department said.The accident occurred around 9.20 a.m. in a well of Heshan coal mine, deputy head of Laibin Municipal Work Safety Bureau Zeng Biao said.

At the time of the blast, some 91 miners were working underground, Zeng said, adding that 66 workers moved to safety. Eighteen miners were helping rescue workers.

The cause of the accident was under investigation, he said.