The explosion occurred around 11:50 p.m. on Tuesday near Pusadian village of Zhen'an County, according to a statement by the county government.
The truck was loaded with 5.28 tonnes of explosives, which were to be unloaded at a warehouse near the village. The vehicle was parked outside the warehouse at the time of explosion.
The truck was registered in central China's Henan Province and was sent by Huatong Chemical Co., Ltd. in Gushi County of Henan. The warehouse belongs to Shaanxi Xiangsheng Group, whose businesses include mining construction and explosion operations.
Seven of the victims were truck drivers, warehouse staff and security guards. One of the 13 injured was discharged from hospital on Thursday. A total of 12 remain hospitalized and one is still in critical condition.
Further investigation is under way.
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