The world's main anti-doping regulator says one of its principal databases has been attacked by a Russian hacking group linked to other notorious computer hacks, including that of the U.S. Democratic Party.
The agency, known as WADA, said on September 13 that the database, which contains a confidential listing of medical submissions made by athletes around the world, had been accessed by a group known as Fancy Bear, and some of the information had already been posted to the Internet.
It said the information had been accessed via a computer account affiliated with the International Olympic Committee.
The cyberattacks were “an attempt to undermine WADA and the global anti-doping system,” Olivier Niggli, the agency's general director, said in a statement.
The attack targeted some female members of the U.S. team which competed at the Rio Olympics last month, including tennis players Venus and Serena Williams and teenage gymnast Simone Biles.
The hackers accessed records detailing Therapeutic Use Exemptions issued by sports federations and national anti-doping organizations that allow athletes to take certain substances due to athletes' verified medical needs.
Fancy Bears has pledged to release confidential records from other national Olympic teams.
Any possible participation of the Russian government or secret services in the hacking of the WADA data "is out of question," Russian news agencies quoted Kremlin spokesman Dmitry Peskov as saying.
The entire Russian Paralympic team and nearly 120 athletes from the country’s Olympic squad were barred from competing in Rio after an investigation found that Moscow ran a state-sponsored sports doping program.
It wasn't immediately clear where the confidential information was being published, though at least one Twitter account called FancyBears purported to be distributing the information.
The hacking group gained widespread notoriety earlier this year when cyber-researchers identified it and another group -- and they appeared to be linked to Russian intelligence services. They were also said to be behind the hack of the U.S. Democratic Party's computer systems. E-mails were later leaked that embarrassed top party leaders and cast a shadow over the Democratic convention.
WADA earlier this year released a damning report detailing a massive government-backed Russian effort to hide positive doping results from its athletes competing at the Sochi Winter Olympics in 2014. The report led to scores of Russian athletes being barred from this year's Summer Olympics in Brazil.
With reporting by Interfax