URUMQI: No radioactive, toxic or viral substances, such as AIDS, were found in blood samples taken from victims of the recent spate of syringe attacks in Urumqi after being tested at a laboratory in Beijing, an expert said yesterday.

But Qian Jun, director of Disease Control and Biological Security Office with China's Academy of Military Medical Sciences, said: "Although no radioactive or toxic substances were found, some patients showed various levels of anxiety and depression and have been recommended for psychological counseling."

On Saturday, the first group of syringe attack suspects went on trial in Urumqi, capital of the Xinjiang Uygur autonomous region, following a series of attacks on at least 500 people in the city since mid-August.