A fire broke out at a Sinopec Shanghai Petrochemical Co Ltd plant in Shanghai early on Saturday, the company said, adding that it had been brought under control.
It was not immediately known if there were any casualties.
Roaring fire was seen engulfing part of a sprawling factory, emitting columns of thick black smoke in a video posted on Twitter by the state-backed Shanghai Daily.
In a post on its official Weibo account, Sinopec said the fire had been “effectively controlled” and it was carrying out “protective burning”.
It said it was also monitoring volatile organic compounds and impact to rainwater outlets, and no impact on the surrounding water environment had been found.
