China’s official news agency, Xinhua, said the blast, at the facility in Kunming, Yunnan Province, took place last Thursday and said that a team from the Guandu district government is still trying to determine the cause of the incident.
This was echoed by the Focusofchina blog, which said the explosion resulted in the evacuation of several nearby offices and a school.
Additionally, the Global Daily reported that a witness “heard the sound of an explosion at 9:50 am Thursday, and then saw flames and heavy smoke surrounding the building.”
The paper went on to say that the incident follows just two weeks after four workers were killed and a further five were injured after an explosion at a pharmaceutical manufacturing facility in Huanggang, Hubei Province.
Quanxin has not yet released a statement on last week's incident.