An explosion at a steel plant in northeastern China killed 13 people and injured another 17, a company official said Tuesday, in the latest industrial accident to hit the country.

The blast happened late Monday when a 10-metre (33-feet) wide mold exploded at the plant owned by state-run Angang Heavy Machinery in Liaoning province's Anshan city, a spokesman for parent company Ansteel Group said.

"The rescue work just finished. The bodies of the three missing workers have been found and now the local work safety bureau is working on the cause of the accident," Song Jiachen told AFP.

The 17 injured had been taken to hospital for treatment, the official Xinhua news agency said, citing local officials, and six of these suffered burns on more than 65 percent of their bodies and were still critical.

The other 11 who were hurt in the accident were in a stable condition, it added.

Workplace accidents are common in China, where bosses frequently ignore safety rules in the quest for higher profits.

Nearly 50,000 people died in work-related accidents in the first nine months of 2011, down 16 percent from the the same period in 2010, figures from the State Administration of Work Safety show.