The head of world athletics vigorously defended the IAAF's anti-doping record, as global sporting bodies called for a thorough probe of the latest allegations to plunge international sport into crisis.
Britain's Sunday Times newspaper and Germany's ARD/WDR broadcaster reported they had obtained secret data from the IAAF, supplied by a whistleblower, that indicated suspicions of widespread blood doping in athletics.
IAAF president Lamine Diack said: "There are allegations made, no evidence. We want to look into them seriously because to say that in athletics between 2001 and 2012 we did not do a serious job with tests is laughable,"
Coming only weeks before track and field's showpiece event, the reports claim endurance runners suspected of doping had been winning a third of the medals at Olympic Games and world championships in that period.
The reports did not say that any athletes had failed doping tests, only that the tests had been abnormal, which can sometimes be a sign of cheating.
The Chief Executive of the Irish Sports Council and former Olympic Marathon Silver Medalist, John Treacy, said he is disappointed but not surprised at allegations published yesterday, of widespread suspected doping in international athletics over an 11 year period.
He told RTÉ's Morning Ireland he would be very skeptical of a lot of athletic performances that he had watched over the years, particularly when athletes from one country dominated an event, as had been outlined regarding athletes form Kenya and Russia.
Mr Treacy said Ireland was no different to any other country and testing programes in Ireland had found evidence of doping and exposed cheating athletes.
He said he believed the Irish authorities were very much on top of it and we had an advantage in that the pool of athletes is relatively small.
Mr Treacy called for the world athletic's body the IAAF to do more to tackle the problem globally.
The allegations are the latest setback to tarnish the multi-billion dollar world of sport after the scandal at soccer's global governing body, FIFA.
Athletics are a central part of the Olympics, the only sporting event that rivals soccer's World Cup in scale and which collects billions of dollars from sponsors like Coca-Cola, Panasonic, Visa and McDonald's.
International Olympic Committee (IOC) President Thomas Bach told reporters today he had spoken to the World Anti-Doping Agency (WADA) head Craig Reedie and had full confidence in that body to investigate the claims thoroughly.
"I don't know about the detailed allegations, which athletes, which competitions are affected," he said.
Mr Bach said the IOC would act with "zero tolerance" if there should be a case involving results at an Olympic Games.
"But at this time we have nothing more than allegations and we have to respect the presumption of innocence for the athletes," he said.
Medals won could be affected if any cases of doping were subsequently unearthed using newer testing techniques that did not exist at the time.
"I do not know what we are dealing with," Senegal's Mr Diack said.
"It is possible if we discover with new techniques that someone doped etcetera, etcetera then yes, otherwise no.”
"But I laughed when I read between 2001 and 2012 IAAF did not do the work," he said.
Arne Ljungqvist, the head of the IOC's medical commission, had worked hard to combat doping in that period, Mr Diack said.
The reports come weeks before a new IAAF president will be elected, with Britain's Sebastian Coe and Sergey Bubka of Ukraine bidding to replace the retiring Diack.
Sheikh Ahmad Al-Fahad Al-Sabah, one of the most influential figures in world sport, appeared sceptical about the timing of the allegations before that election.
The Kuwaiti, who is the head of the Olympic Council of Asia and the Association of National Olympic Committees, told Reuters: "I'm hearing all those news (but) I don't have the big picture.
"If there is some mess I hope it will be solved by the mechanism of the governance and anti-doping. If not, related to election time I will understand it," he said.
Earlier, US anti-doping agency Chief Executive Travis Tygart said an "aggressive review" was needed to protect clean athletes. WADA has said it was "very disturbed" by the reports.
"This is more evidence of what many of us already suspected," Mr Tygart told Reuters.
The IAAF noted that the reports were based on confidential information obtained without permission. A heavy preponderance of the "abnormal" results were from Russian athletes, according to the media reports.
Russian sports minister Vitaly Mutko said the allegations had "nothing to do with Russia" and that they reflected a power battle before the IAAF leadership vote.
The IAAF's world athletics championships begin in Beijing on 22 August.
In the report, Australian doping expert Robin Parisotto and another scientist, Michael Ashendon, said more than 800 athletes had recorded one or more "abnormal" results, defined as a result that had less than one chance in 100 of being natural.
Such athletes accounted for 146 medals at top events, including 55 golds, the Sunday Times said.
"There were 800-odd abnormal or suspicious results but not all of those would have been truly indicative of doping," Mr Parisotto told Reuters.
Factors such as the timing of tests, altitude and testing conditions could have led to some suspicious results.
"But there were values that were ... quite extreme and even taking into consideration confounding factors, there was really no disputing what that data was telling us," Mr Parisotto said.
Blood tests were not used as an official sanctioning tool until 2009 but the leaked data still showed a high number of suspicious or abnormal test results subsequently, he said.
"There are real questions to be asked if there is no action taken, particularly for the results taken post-2009," Mr Parisotto said.
"Some of the values in these athletes were so extreme that they were downright dangerous and the risks to their health were indisputable."
Russia accounted for 415 abnormal tests, followed distantly by Ukraine, Morocco, Spain, Kenya, Turkey and others.
"A remarkable 80% of Russia's medal winners had recorded suspicious scores at some point in their careers," the Sunday Times said.
The allegations concern techniques to improve the ability of blood to carry oxygen, which can give an advantage in endurance events like cycling or running over medium and long distances.
The Sunday Times and ARD said they were given access to the results of more than 12,000 tests of more than 5,000 athletes taken between 2001 and 2012.
The two experts concluded distance running was in the same state as cycling had been when Lance Armstrong won the seven Tour de France victories of which he has since been stripped.
"So many athletes appear to have doped with impunity, and it is damning that the IAAF appears to have sat idly by and let this happen," Mr Parisotto, an inventor of the test used to detect the blood doping agent EPO, told the Sunday Times.