The International Olympics Committee (IOC) will take a "zero tolerance" approach should accusations of large-scale doping in track and field be proved, says its president Thomas Bach.
German broadcaster ARD and The Sunday Times newspaper claim to have seen a database of 12,000 blood tests from approximately 5,000 athletes between 2001 and 2012, with The Times saying that the results showed the "extraordinary extent of cheating" by "elite athletes."
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The World Anti-Doping Agency is "very disturbed" by the allegations, while the International Association of Athletics Federation has threatened that legal action could be taken after claiming the data was obtained illegally.
Bach has now had his say, and warned that any wrongdoers will be punished.
"At this time we've nothing more than allegations and we have to respect the presumption of innocence," he said.
"If there should be cases involving results at Olympic Games, the IOC will act with zero tolerance with our usual policy.
"We have full confidence in the inquiry by WADA. If needed, we will follow suit and do everything to protect clean athletes."
Seb Coe, who is running for the presidency of the IAAF at this month's elections, says the body will provide a "robust response."
"In response to the media reports, I know that the IAAF takes these allegations extremely serious and it will issue a robust and detailed response to them and continue to work closely, as it has always done, with WADA," he wrote on Twitter.