 Image copyright AP Image caption Simone Biles' confidential medical data has been released 
 
 The World Anti-Doping Agency (Wada) has condemned Russian hackers for leaking confidential medical files of star US Olympic athletes. On Monday, the group began posting confidential information about noteworthy U.S. Olympic athletes — tennis stars Serena and Venus Williams, four-time gymnastics gold medalist Simone Biles and women’s basketball standout Elena Delle Donne — and promised more leaks would be forthcoming. What we’re seeing here is a digital temper tantrum.” 
 
 The information released mostly involves Therapeutic Use Exemptions, situations in which WADA allows athletes to take certain banned substances if they’re used to treat legitimate medical issues. “Wada deeply regrets this situation and is very conscious of the threat that it represents to athletes whose confidential information has been divulged.” 
 
 The agency said it believed the hack was carried out using spear-phishing emails to gather passwords for the Wada Anti-Doping Administration and Management System (Adams) database.
– In what one analyst calls a "digital temper tantrum," hackers linked to the Russian government have hacked into the World Anti-Doping Agency's Olympic database and released information on star American athletes, including Serena and Venus Williams. WADA has confirmed the security breach, and the hacking group "Fancy Bears"—which was apparently motivated by revenge for WADA's exposure of state-sponsored Russian doping—says there are more leaks to come, the Washington Post reports. A roundup of developments: Fancy Bears also posted information on gymnast Simone Biles and basketball player Elena Delle Donne relating to "Therapeutic Use Exemptions" that allow athletes to use banned substances for valid medical reasons, the Independent reports. The hackers claimed the exemptions were "licenses for doping." WADA says it believes the attacks were carried out with a "spear-phishing" attack that gathered passwords with emails to authorized users that convinced them to click on infected links. According to the leaked documents, Biles uses medication to treat ADHD. "Having ADHD, and taking medicine for it is nothing to be ashamed of" and "nothing that I'm afraid to let people know," she tweeted in response. Venus Williams, who was diagnosed with the autoimmune disease Sjogren's syndrome in 2011, issued a statement saying she followed all the rules and was disappointed "that my private, medical data has been compromised by hackers and published without my permission." The Fancy Bears group is believed to be linked to the Russian military intelligence agency suspected of hacking the DNC, reports the New York Times, which notes that the Kremlin "has gone to to great lengths to maintain plausible deniability in matters of espionage"—and denies involvement in the WADA hack. The hackers are "trying to sow doubt over the integrity of the individual athletes and the various Olympic bodies and watchdog groups," Rich Barger of cybersecurity firm ThreatConnect tells the Post. "It's just ultimately sour grapes. What we're seeing here is a digital temper tantrum." US Anti-Doping Agency chief Travis Tygart called the hack "cowardly and despicable," saying that the athletes involved had "done everything right in adhering to the global rules for obtaining permission to use a needed medication," the BBC reports. Fancy Bears, which claims to be allied with Anonymous, says it will release information on other countries' athletes this week, reports the AP, which found that a French phone number provided by the group was bogus and the mailing address it gave was that of a florist east of Paris.