The suspect, identified as Fan Jieming, went on trial in a court in Shanghai, where the shootings occurred last June, China Daily reported. He is accused of intentional homicide, robbery, robbery of firearms and illegal trade and possession of firearms and ammunition.
The prosecution told the court police seized a shotgun, a rifle and three air rifles when they captured the suspect at the Shanghai Guangyu Fine Chemical Co., where plant boss Li Zhizhong and three employees were killed. The report said two more people were later killed and another four were injured.
Li, who set up the plant in 2001, later sold half of the business to Fan Guofu, who then asked his uncle Fan Jieming to become office director of the business, the report said.
However, Fan Jieming told the court there had been continuing disputes since he took over and claimed some of the victims had "caused trouble to my management of the factory," the report said. He was quoted as saying some of the victims broke the locks of the warehouses and changed the locks of the factory's two gates.
The prosecution said one of the victims was beaten to death with an iron pipe after acid was sprayed on his face.
"I don't agree with the prosecutors. I didn't plan to kill him, and it was caused by a sudden impulse," Fan Jieming was quoted as telling the court.
Among other dead victims, Fan is accused of killing a taxi driver after the driver refused to part with his vehicle.
"But when I asked him to go away and leave the car for me, he said he wasn't frightened by a gun replica, so I shot him," Fan was quoted as saying.