Police in Jiangsu province said the person they suspect shot and killed a man during a robbery on Friday is also believed to be responsible for a series of robberies and shootings.
The Public Security Bureau of Nanjing, in the provincial capital, has distributed a photo of the suspect publicly and is offering a reward of 100,000 yuan ($15,840) for information that could lead to his arrest, said Pei Jun, deputy chief of the bureau.
Comparing photographs of the suspect wanted in the shooting and robbery on Friday and in a series of similar crimes in Changsha and Chongqing, Pei concluded that it is "very likely" they are of the same person.
On Friday, the suspect is believed to have robbed and shot the victim, surnamed Cheng, at 9:50 am on Dongmen Street in Nanjing's Xiaguan District. The suspect fled the scene after stopping a vehicle and getting into it.
Cheng, 42, was robbed shortly after he had withdrawn 200,000 yuan in cash from a bank, Pei said.
The victim was rushed to a hospital, where he died, while the police were sent out to track down the suspect.
The police released information about the suspect and two photographs of him on the Internet. They said he is about 40 years old, stands about 1.7 meters tall and has dark skin and a medium build. The suspect in the shooting on Friday was wearing dark clothes and his feet turned out when he walked. He spoke Mandarin with an accent.
Meanwhile, the suspect is believed to have used a gun to kill six people and injure another two in six robbery cases in Changsha, the capital of Hunan province, and in Chongqing since 2004, Pei said.
In Hunan, the police have offered a 300,000-yuan reward to anyone who helps them to hunt down the suspect.
Since gun violence is rare in China, where it is illegal to possess a firearm, the recent attack has drawn much attention,.
The only significant exception to the rule gives hunters the right to own guns, but only after they have gone through a lengthy application process.
Witnesses of the crime said they had seen a man rush up to the victim and shoot him down without giving a warning. They heard a loud bang, like the sound of a firecracker going off, the China News Service reported, citing a witness whose full name was not printed.
The witness said she saw the victim lying down on the ground in a pool of blood. The police arrived soon afterward.
On Friday, Nanjing publicity officials said the police had received tips that the suspect might be aboard a certain bus and that they had stopped the vehicle at a toll station, only to find that he was not on it.
The officials said the victim is a resident of the city and worked for a construction materials company.