A group of Russian hackers has leaked the medical files of athletes such as Venus and Serena Williams as well as Simone Biles.
The trio won four gold medals between them and the group of hackers, also known as 'Fancy Bears', wanted to expose them.
"After detailed studying of the hacked WADA databases we figured out that dozens of American athletes had tested positive," said the group on its website.
"The Rio Olympic medallists regularly used illicit strong drugs justified by certificates of approval for therapeutic use. In other words they just got their licenses for doping. This is other evidence that Wada and IOC's Medical and Scientific Department are corrupt and deceitful."
The group reportedly gained access to the anti-doping administration and management system (ADAMS) database via an International Olympic Committee-created account for the Rio 2016 Games.
Meanwhile, the World Anti-Doping Agency released a statement in response.
"The group accessed athlete data, including confidential medical data – such as Therapeutic Use Exemptions delivered by International Sports Federations and National Anti-Doping Organizations (NADOs)– related to the Rio Games; and, subsequently released some of the data in the public domain, accompanied by the threat that they will release more.
"While it is an evolving situation, at present, we believe that access to ADAMS was obtained through spear phishing of email accounts; whereby, ADAMS passwords were obtained enabling access to ADAMS account information confined to the Rio 2016 Games. At present, we have no reason to believe that other ADAMS data has been compromised.
“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. We are reaching out to stakeholders, such as the IOC, IFs and NADOs, regarding the specific athletes impacted.”