Doping violations have increased in China ahead of this year's National Games with eight athletes testing positive in the second quarter of the year, the country's anti-doping authorities said on Wednesday.
A total of 12 positive cases have been registered this year, already matching the number of violations in 2012, China's Anti-Doping Agency said.
"The number of positive cases has largely increased compared with that of last year, which sent us a warning," anti-doping chief He Zhenwen told the Xinhua news agency.
The 11th version of the inter-provincial National Games attracted 15,133 athletes from 46 teams competing in 362 events in 33 sports in Jinan, Shandong Province in 2009.
The quadrennial event, first held in 1959 in Beijing when Communist China was isolated from most of the rest of the sporting world, remains the major way the government appraises the work of provincial sports authorities.
Funding for the provinces is largely based on their success at the Games, which has encouraged cheating through doping and falsifying the age of athletes in the past.
"There always will be someone who risks doping for unfair advantage when the return is lucrative," He added.
"History taught us that the National Games could well be the reason for cheating."
China's women's 100 meters champion Wang Jing was banned for life after she tested positive for the performance-enhancing metabolites epitestosterone and testosterone after winning the 100m race at the 2009 Games in Jinan, Shandong province.
In 2005, Sun Yingjie, a former world championship bronze medalist, tested positive after finishing second in the 10,000m -- a day after winning the Beijing Marathon.
Eleven athletes failed dope tests, while three field athletes and a swimmer pulled out after "abnormal" results in the 2001 edition.
This year's Games will be held in Shenyang, the capital of the northern province of Liaoning - one of the country's sporting powerhouses - from August 31-September 12.
(Reporting by Sudipto Ganguly in Mumbai; editing by Nick Mulvenney)