Seven hundred and eighteen people have been detained for being implicated in the Urumqi riot on July 5 which left 197 people dead and more than 1,600 injured, Urumqi City police chief Chen Zhuangwei said Tuesday.

Chen Zhuangwei (C), head of the Public Security Bureau of Urumqi City, addresses a press conference in Urumqi, capital of Xinjiang Uygur Autonomous Region in northwest China, Aug. 4, 2009. (Xinhua/Sadat)

Chen, head of the Public Security Department of Urumqi, capital of the Xinjiang Uygur Autonomous Region, said evidence collection had been a heavy load for the city's police force. It had involved examinations at the crime scenes and DNA evaluations, but it had been carried out swiftly.

Chen said police had visited more than 1,000 people, including those injured in the riot and families whose members had lost their lives in the unrest. Police had also inspected 530 shops and 943 motor vehicles damaged during the violence. As well, they collected and examined 3,318 pieces of evidence, and obtained 2,169 photos of crime scenes in Urumqi.