The spontaneous combustion of substandard explosives led to the hospital blast that has so far left 32 people dead in north China's Shanxi Province, provincial police said on Monday.

Investigations show that the explosives contained chlorate, which easily produces heat when mixed with other elements and finally leads to combustion, a source with the Shanxi Provincial Public Security Department said.

The blast occurred at about 2:25 AM last Monday at the staff hospital affiliated to the Xuangang Coal and Electricity Company in Yuanping. A two-storey hospital building and several adjacent small houses were flattened in the accident.

30 people are still recovering in hospital.

Two suspects, Wang Jinsheng, an administrative officer of the hospital to whom the explosives belonged, and his chauffeur Wang Guohua surrendered to police last Thursday. Another suspect surnamed Xing, who allegedly helped to transport the explosives, has also been detained by police.

According to a police statement, Wang Jinsheng admitted to storing more than two tons of explosives in a hospital garage with the help of Wang Guohua. Wang had bought the explosives for use in his private coalmine.

Police are still looking for a fourth person by the name of Qi Er, who they say sold the explosives to Wang.

In the meantime, compensation for the victims' relatives is being worked out, according to local government and company sources.

(Xinhua News Agency April 18, 2006)