BEIJING, Aug. 21 (Xinhua) -- China's anti-doping authorities Wednesday said eight athletes tested positive in the second quarter of the year, including one through the biological passport.

By far there have been 12 doping cases this year, leveling the total of last year.

China's Anti-Doping Agency (CHINADA) said the rise in number of positive cases may have something to do with the approaching Chinese National Games.

"The number of positive cases largely increased compared with that of last year, which sent us a warning," said CHINADA head He Zhenwen.

"There always will be someone who risks doping for unfair advantage when the return is lucrative," said He. "History told us that the national games could well be the reason for cheating."