Federal Security Service (FSB), Russian’s internal intelligence agency, helped Dr. Grigory Rodchenkov tamper with Olympic athletes’ urine samples.

Dr. Rodchenkov headed Russia’s antidoping laboratory and has been considered as a performance enhancement drug expert, being invited to talk about the topic in international conferences. However, with World Anti-Doping Agency’s (WADA) report findings, Dr. Rodchenkov was identified as a key person who facilitated tampering with the athletes’ urine samples.

And tamper with the urine samples he did. In a New York Times report, Dr. Rodchenkov detailed how the they were able to get past through standard issue Berlinger self-locking containers that once were thought to be tamper-proof. A man Dr. Rodchenkov thinks works for the FSB showed up at their lab as early as 2013 when preparations for the Sochi Winter Olympics began and asked about the bottles whose lock comprised of toothed metal rings.

After some time, the FSB man presented to him an unlocked bottle with the cap intact. It was a reverse-engineering marvel that would massively help Dr. Rodchenkov and his team in a makeshift laboratory while the Sochi Olympics were in full swing.

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In room 124, the swapping of contaminated urine was done through a circular hole with the help of the unidentified and assumed FSB agent. There the world-acclaimed expert on doping cleaned the bottles and replaced it with previously collected clean urine samples from identified athletes . Before daybreak, the B set of urine samples were magically restored in the security-tight storage room.

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Through Rodchenkov’s admission and accompanying strong proof of tampering such as e-mails and a spreadsheet containing a list of athletes he helped clean samples for, the International Olympic Committee has since called WADA to investigate this elaborate cheating immediately.

Meanwhile, USA Today reports that Russian sports minister Vitaly Mutko gave a press conference ahead of Times’ publication of the story to denounce it and say that the accusations were baseless.