An explosion tore through a chemical plant in central China’s Anhui province on Wednesday, creating a mushroom cloud in the night sky.

State media reported that two on-duty staff suffered minor injuries from glass shards in the blast, which occurred at the Hengxing Chemicals plant in Tongling city at around 10:50pm.

Photo: Weibo.

Local media initially reported that the blast was caused by “barrels of solvents with a high boiling point.” State-run news wire Xinhua said that the explosion appeared to be caused by acetone, and that officials might have to clear out dangerous chemicals.

Later, the Tongling police chief said that the blast was caused by inflammables and oils, and not dangerous chemicals.

Beijing News reported that local environmental authorities had ordered the private-owned plant to cease production last October, following a spot inspection on pollutants.

However, the same authorities had assessed Tongling Hengxing Chemicals as one of 89 “good environmental enterprises” in the city earlier in 2015.