Workers and a heavy equipment work at the blast site of a workshop in the Angang Heavy Machinery Co., Ltd. in Anshan City, northeast China's Liaoning Province, Feb. 21, 2012. A blast occurred at 11:30 p.m. Monday (0330 GMT) at a steel-casting workshop owned by Angang Heavy Machinery Co., Ltd., leaving 13 people dead, one missing and 17 injured. (Xinhua/Yang Qing)

The death toll from a blast at a state-owned steel plant Monday night in northeast China's Liaoning Province has risen to 13, said local authorities and rescuers Tuesday.

The accident happened when a mold exploded at 11:30 p.m. Monday at a steel-casting workshop owned by Angang Heavy Machinery Co., Ltd. in the city of Anshan, according to a statement issued by the publicity department of the provincial committee of the Communist Party of China.

Ten people were found dead as of early Tuesday, while rescuers recovered the bodies of three workers who were previously identified as missing in the blast by Tuesday noon.

Another 17 people were injured in the blast and they were receiving medical treatment in hospital, said the statement.

Rescuers are searching for the missing worker. The cause of the accident is under investigation.

The state-run Angang Heavy Machinery Co., Ltd. founded more than 70 years ago, is one of China's largest machine manufacturers in the metallurgy industry, according to the company's website.