BEIJING (Reuters) - Chinese officials insist tough new eligibility rules will put a stop to the type of "age cheat" scandal that saw a gymnast stripped of her Olympic medal.

Dong Fangxiao had to return her women's gymnastics team bronze medal from the 2000 Sydney Olympics earlier this year following an International Olympic Committee (IOC) probe.

Chinese sports officials promised that tighter checks introduced after the scandal would eradicate the problem.

China's delegation chief for next month's Youth Olympic Games in Singapore said the country had adopted a zero tolerance policy toward potential cheats.

"We've scrutinized every athlete's age for the Youth Olympic Games to make sure there is no one going to Singapore with a fake age," Cai Zhenhua told Thursday's China Daily.

"We have to make our Chinese delegation very clean and transparent. This is for the benefit of the athletes and the fair play spirit of the Olympics."

The inaugural Youth Olympics in Singapore begin on August 14 and showcases potential future senior Olympic athletes aged from 14 to 18.

Stringent documentation checks on China's 70-strong squad have been carried out in addition to X-ray bone analysis on the team's under-16s, Cai added.

Suspicions of age-faking have dogged Chinese sport for years.

Dong registered different ages at Sydney and the 2008 Beijing Games, where she served as a technical official.

Her five team mates -- Yang Yun, Liu Xuan, Ling Jie, Huang Mandan, Kui Yuanyuan -- also lost their medals.

At the 2008 Beijing Olympics, China's He Kexin, a women's team and uneven bars gold medalist, was also investigated but subsequently passed as eligible.

(Reporting by Alastair Himmer in Tokyo. Editing by Peter Rutherford)