TAIYUAN, Oct. 20 (Xinhua) -- Four people have been confirmed dead and another injured in a gas explosion in a coal mine in north China's Shanxi Province, according to local authorities on Tuesday.

The explosion happened in the mine owned by Lu'an Group at around 2 a.m. Tuesday. The rescue work has ended. An investigation into the cause of the blast is under way.

The mine has an annual production capacity of 1.2 million tonnes.