The illegal production of detonators was blamed for a blast that left two dead and two others injured in an apartment building in central China's Henan Province, police said Saturday.

The explosion ripped through the seven-story building at about 10:50 a.m. Friday in the Wancheng District in Nanyang City, about 300 km southwest of the provincial capital of Zhengzhou

The explosion took place on the first floor and damaged rooms on the two floors above. It also shattered windows on other floors and nearby buildings, including a kindergarten.

Residents in the building were forced to be evacuated after the blast.

The latest investigation indicates that 52-year-old Xu Baocheng and his paramour, 38-year-old Lu Xiaohong, had rented the room on the first floor in the building to manufacture detonators illegally, said Ma Jianfeng, deputy director of the Nanyang Municipal Public Security Bureau.

"They had made more than 1,000 detonators, most of which blew up in the explosion," he said.

A female friend of Lu, 35-year-old Cui Honghua, visited Lu Friday morning, and the explosion occurred when Lu went to the washroom, Ma said.

Xu and Cui were killed instantly, but Lu ran away from the scene with minor injuries, Ma said.

Lu surrendered to police Friday night, he said.

The other injured resident was identified as 40-year-old Gao Feiyan who lives on the second floor. She fell from the floor when the blast happened. She is being treated at a local hospital and described as being in stable condition, Ma said.

No children in the nearby kindergarten was injured, he added.

(Xinhua News Agency March 8, 2009)