?Lanzhou police in northwest China's Gansu Province on Wednesday offered a reward of 100,000 yuan (14,600 U.S. dollars) for a man who shot dead a policeman.

The suspect has been identified as Fu Xiaolin, a vegetable wholesaler from the outskirts of Xi'an, capital of northwest China's Shaanxi Province. He sold vegetable at a wholesale market in Lanzhou, capital of Gansu.

Police said Fu fired at the policeman Dou Yong with a handgun and fled.

Dou was among a group of policeman sent to investigate Fu at 8:20 a.m. Tuesday, after Fu's wife came to the police station in Weiyuan Street, Lanzhou City, to report she was threatened by Fu with a handgun, because the husband suspected she was having an affair.

Lanzhou police have tightened security at checkpoints on all major roads out of the city.