The World Anti-Doping Agency (WADA) has confirmed that a group of Russian hackers has leaked information on tennis stars Venus and Serena Williams, U.S. teenage gymnast Simone Biles and U.S. basketball player Elena Delle Donne.
The hacker group Fancy Bear released the information from a database set up for the Rio Olympics on Tuesday. The information involved confidential medical data for the four athletes which included positive tests for certain banned substances, allowed by WADA as a therapeutic use exemptions. The exemptions are allowed only when the medication is required to treat an illness or condition, according to WADA’s website.
Fancy Bear said all four athletes were taking banned substances, and on its website called the exemptions “licenses for doping.”
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The hacker group also threatened to release more data in the coming days.
Nineteen-year-old Biles, who won four gold medals, including the gymnastic women’s individual all-around, has publicly announced she has attention deficit hyperactivity disorder (ADHD) in the wake of the attack.
“I have ADHD and I have taken medicine for it since I was a kid,” she wrote on Twitter.
“Please know I believe in clean sport, have always followed the rules, and will continue to do so as fair play is critical to sport and is very important to me.”
In the leaked documents, Biles was shown to have tested positive for methylphenidate, commonly known as Ritalin, which is used in the treatment of ADHD.
Venus Williams also acknowledged she had been granted an exemption, but didn’t give a reason for the medication.
“I am one of the strongest supporters of maintaining the highest level of integrity in competitive sport and I have been highly disciplined in following the guidelines,” she said in a statement to WTA Insider.
Delle Donne also took to Twitter in a sarcastic tone to condemn the hackers.
“I’d like to thank the hackers for making the world aware that I legally take a prescription for a condition I’ve been diagnosed with … Thanks guys!” she wrote.
There has been no statement from Serena Williams.
“WADA deeply regrets this situation and is very conscious of the threat that it represents to athletes whose confidential information has been divulged through this criminal act,” Olivier Niggli, director general of WADA, said in a release.
Niggli also said the fact that the hackers were Russian doesn’t bode well for the current investigation into Russia’s state-wide doping scandal.
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“Let it be known that these criminal acts are greatly compromising the effort by the global anti-doping community to re-establish trust in Russia further to the outcomes of the agency’s independent McLaren Investigation Report,” he said.
A spokesman for Russian President Vladimir Putin rejected WADA’s statement blaming Russian hackers as unfounded.
“There can be no talk about any official or government involvement, any involvement of Russian agencies in those actions. It’s absolutely out of the question,” spokesman Dmitry Peskov said in a statement carried by Russian news agencies.
“Such unfounded accusations don’t befit any organization, if they aren’t backed by substance.”
*with files from The Associated Press