NANJING - Over 13,000 police officers have been dispatched to search for a male suspect who shot and robbed a man in front of a bank in an East China city on Friday, local police said Saturday.

The Public Security Bureau of Nanjing, the capital city of Jiangsu province, has upgraded its city alert to the first-level and initiated a blanket search for the suspect in the armed robbery case.

Armed police stand outside the Nanjing Railway Station on Jan 7 as a city-wide search was launched to capture a suspect in a recent high-profile armed robbery. [Photo/CFP]

Special armed police and police cars have blocked all major and secondary roads, with many others searching in public places. Two helicopters have also been dispatched to search for the suspect.

The Public Security Bureau has tightened security in banking outlets and self-service areas, and offered escorts to people making large withdrawals.

As of 4 pm Saturday, over 240 tips had been poured in by citizens and the case remained under investigation.

Police have offered a reward of 100,000 yuan ($15,850) for information leading to the arrest of the man, who is also suspected of being involved in six cases of homicide and armed robbery that took place in two cities over the last seven years.

The suspect, a man believed to be in his 40s, shot a man who had just finished withdrawing 200,000 yuan in front of a bank on Nanjing's Dongmen Street at 9:50 am Friday. The robber then took the money and hopped in a car that sped away from the scene of the crime, Pei Jun, the bureau's deputy chief, said on Friday.

Pei said the suspect is believed to have used a gun to kill six people and injure another two in six robberies that took place in Changsha, the capital of Hunan province, and Chongqing municipality since 2004.

Firearm possession is illegal in China.