The blast occurred at about 9:30 am on Wednesday at Fuwa Engineering Machinery Manufacturing Co. Ltd. in the Shunde District of the industrial city of Foshan, killing 17 people and injuring another 33.
As of Saturday noon, 11 were in critical condition and 17 were slightly injured. Four have left hospital after treatment, according to a statement from the Foshan district government.
Fuwa, founded in 1997, is a global trailer axle and chassis component manufacturer. It was expected to invest 2.26 billion yuan (370 million US dollars) to build its headquarters in Foshan, Xinhua reported.