A Kenyan athletics coach has been sent home from Rio after posing as an athlete and giving a urine sample.
Kenya said sprint coach John Anzrah "presented himself" as 800m medal hope Ferguson Rotich and "even signed the documents" for the doping test.
"We cannot tolerate such behaviour," said Kip Keino, chairman of the National Olympic Committee of Kenya.
Meanwhile, athletics' governing body has suspended Kenyan official Michael Rotich over corruption allegations.
The country's track manager was sent home from Rio following newspaper allegations that he was prepared to warn coaches about drugs tests in return for £10,000.
He appeared in court in Nairobi earlier this week where a Kenyan magistrate ruled he can be held by police for four weeks as they investigate the claims.
Michael Rotich denies any wrongdoing, saying he wanted to protect athletes.
The IAAF said it was suspending him for 180 days while it carries out its own investigation.
Athlete Ferguson Rotich, who finished fourth at last year's World Championships in Beijing, qualified second in his heat on Friday.
The athlete's agent, Marc Corstjens, said Rotich lent Anzrah his pass so the coach could get a free breakfast in the Olympic Village on Wednesday.
Anzrah, 61, was then allegedly approached by a doping control officer who was looking for Rotich and asked to provide a urine sample, which the coach did.
"Ferguson is completely confused as to why he would do this but the good news is that he found out straight away and went to the drug-tester and gave them blood and urine samples," said Corstjens.
The International Olympic Committee has opened disciplinary proceedings into the matter, but praised Kenya's Olympic body for its "swift action".
Chairman Keino said the committee had not facilitated Anzrah's travel to Brazil, adding: "We don't even know how he came here."
Subscribe to the BBC Sport newsletter to get our pick of news, features and video sent to your inbox.