Russia wasn’t the only country with a state-sponsored athletics doping program, the South China Morning Post reported on Thursday. Athletes from China, specifically those who were members of “Ma’s Army” under coach Ma Junwen—a group which included world-record holder and Olympic medalist Wang Junxia—were forced to take large doses of illegal drugs, according to a never-before-seen letter written by Junxia and her teammates to a Chinese journalist Zhao Yu.

“For many years, [he] forced us to take a large dose of illegal drugs. It was true,” one of the athletes wrote in the letter, which has remained unpublished for 19 years.

Several of Junwen’s athletes set world records during the 1990s, but it was Junxia stood out. In 1993, Junxia went on a tear, setting her personal best of 2:24:07 in the marathon and winning the world title in the 10,000m—the latter capping off a Chinese sweep of the distance events at the world championships in Stuttgart. Most impressive, however, were her performances at the Chinese National Games in September. Junxia took silver in the 1500m behind training partner Qu Yunxia—3:50.46 to 3:51.92—with both marks breaking the previous world record. Later in those games, Junxia ran a world-record of 8:06.11 in the 3,000m and 29:31.78 in the 10,000m, taking a mind-blowing 42 seconds off Norwegian Ingrid Kristiansen’s previous mark. Both of those records still stand today. Wang, who was coached by Junwen until 1995, won gold in the 5,000m at the 1996 Olympics in Atlanta.

According to the South China Morning Post, the IAAF—which inducted Junxia to its Hall of Fame for her achievements during the 1993 season—is investigating the authenticity of the letter before deciding to take action. If the letter is verified and Junxia admits to wrongdoing, she could have results, records and medals taken away from her, along with potential financial penalties, per World Anti-Doping Agency rules.

“Our feelings are sorry and complex when exposing his (Ma’s) deeds,” the letter continued. “We are also worried that we would harm our country’s fame and reduce the worth of the gold medals we have worked very hard to get.”

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