Stringent measures will be in place to control doping at the 12th National Games, a senior anti-doping official said, as authorities announced on Wednesday that eight Chinese athletes failed drug tests in the second quarter of the year.

"Since last year, we have conducted more special doping tests of the athletes who will take part in the National Games," Zhao Jian, vice-director of China's Anti-Doping Agency, told China Daily.

"Officially, we will use the biological passport program during the National Games for the first time."