The blasts occurred between 2 p.m. and 3 p.m. (0600 GMT and 0700 GMT) at the Jilin Petroleum and Chemical Company in the northeastern province of Jilin, the official Xinhua News Agency said.
The cause was under investigation, said a man who answered the telephone at the local government office in Jilin City, where the explosions occurred. He refused to give his name, but said "leaders were directing rescue work at the blast site."
He said the numbers of deaths and injuries were "unclear."
The blasts shattered windows of buildings up to 200 meters (650 feet) away, Xinhua said.
"More than 10,000 residents have evacuated for fear of further explosions and pollution by chemical matters," AP reported.
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