BEIJING (AP) — The IAAF is investigating the authenticity of a two-decade-old letter published in Chinese media that suggests state-sanctioned doping in the 1990s, and casts doubt on the longstanding world records set by Wang Junxia in the women's 3,000 and 10,000 meters.

Wang's records could be annulled if the former Olympic and world champion has admitted to doping before setting the marks in 1993, the International Association of Athletics Federations said Friday.

Chinese website Tencent reported that Wang wrote a letter, signed by nine other members of coach Ma Junren's training program, in 1995 to journalist Zhao Yu allegedly revealing that athletes were forced to take banned substances and Ma injected athletes himself.

"It's all true that Coach Ma had beaten, verbally abused and mistreated us for years," said the letter, dated March 28, 1995. "It's also true that he had coaxed or forced us into using large quantities of banned drugs.

"His crimes must be revealed because we don't want to see the same thing to happen to the next generation," according to the letter. "Such inhumane tortures have brought us to the brink of a complete collapse."

The IAAF issued a statement on Friday saying it only became aware of the allegations when contacted by Chinese media, and has asked the Chinese Athletics Association to assist with an investigation to verify if the letter — which is written in Chinese and which Zhao provided to Tencent this week — is genuine.

"If an athlete has admitted that, at some time prior to achieving a world record, he had used or taken advantage of a substance or technique prohibited at that time, then, subject to the advice of the medical and anti-doping commission, such record will not continue to be regarded as a world record by the IAAF," the statement said.

A woman who answered the call at the Chinese Athletics Association said she had no knowledge of the case.

The scandal resurfaced this month in China, when social media began heated discussions on doping following a recently-published chapter about Ma's track team, which was known collectively as "Ma's Army."

The chapter had been banned for years but was printed in 2014 when publishing authorities believed the Chinese public would be able to accept the scandal, Zhao told the Chinese media.

Ma and his team were considered national heroes for winning medals and setting records at world events, which was then considered a paramount national pride not to be questioned.

In 2008, Wang denied doping in an interview with The Associated Press, ascribing her record times to her youth, health and a brutal training regimen.

Drug tests then turned up no incriminating evidence, and Ma had claimed Wang was fed nothing more than turtle blood, ginseng and a stamina-boosting fungus.

In the chapter, Zhao wrote that the distance runners under Ma were deeply troubled by the use of the performance-enhancing drugs but were too afraid to speak up because national honor was at stake. Zhao wrote that the practice began before 1990 and that Ma used the drugs extensively on the athletes after 1991.

He explained the team fell apart at the end of 1994 when the national swimming team got hit with doping scandals and that the runners — after leaving Ma's program — saw their performances plunge.

Just ahead of the 2000 Sydney Games, Ma's team was prohibited from competing, even though seven members qualified.

Nine years later, a senior Chinese sports official revealed that an internal doping test showed six of the seven runners from Ma's program were most likely to have been using drugs.

Wang clocked 29 minutes, 31.78 seconds at China's national games in September 1993, shattering the 10,000-meter mark by 42 seconds. No runner has come within 22 seconds of her time since then.

Wang's record in the 3,000 is 8:06.11, also set at the 1993 national games. Wang won gold in the 10,000 at the 1993 world championships and in the 5,000 at the 1996 Atlanta Olympics.