The firecracker factory explosionin east China's Jiangxi Province on June 9 that left 16 people dead and three injured was caused by illegal operation and poor management, investigators said Friday.

The staff of Huayuan Firecracker Mill in Luxi County stored 170 kilograms of dynamite in the workshop where the explosion happened, in violation of the factory regulation that only 2.5 kilograms of dynamite is allowed to be kept in the workshop, according to the investigation team.

Zeng Hailin, manager of the mill, used an encasing workshop for transferring dynamite storage and built a shelter for saltpeter loading illegally. He also let workers increase the dosage of dynamite in firecrackers and use potassium chlorate, which had been banned by the Ministry of Public Security.

Zeng has been detained by the police.

Besides, the workers had no certificates for the job and they also breached regulations on the job procedure. But the supervision department neglected the hidden risks, which finally caused the explosion, according to the investigation team.

Source: Xinhua