About 160 miners were trapped by a colliery explosion Sunday night in northeast China's Heilongjiang Province, the local coal mine safety watchdog said early on Monday.

The blast was reported at around 9:00 p.m. at Dongfeng Coal Mine run by Qitaihe branch of the Heilongjiang Longmei Mining (Group) Co., Ltd., the provincial coal mine safety administration told Xinhua.

More than 40 miners have managed to escape the site overnight, but the roll book says at least 200 were working underground when the blast went off.

Rescue work is going on, and management of the mine is trying to work out the exact number of the trapped miners.

Longmei Group is a mining conglomerate of four state-owned major coal businesses in the northeastern province. It has a registered capital of 13 billion yuan (1.6 billion US dollars).

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