LONDON (AP) - Usain Bolt says the announcement of positive retesting of samples from the 2008 Beijing Olympics is "really bad news."
The Jamaican great says "for me, it's rough, it's rough in the sport. Something that's been tarnishing the sport for years."
Bolt was speaking to reporters in Prague on Wednesday, a day after the International Olympic Committee announced that 31 athletes were caught and could be barred from competing in the Rio de Janeiro Games.
Bolt still says the agencies like WADA "are doing a very good job of cleaning up the sport. They've proven that anybody who has cheated, they're going to catch."
Bolt will run the 100 meters at the Golden Spike meet in the eastern Czech city of Ostrava on Friday, his first race in Europe ahead of the Rio Games.
The IOC says final results on the retesting of doping samples from the 2008 Beijing Olympics will be known early next month.
The International Olympic Committee announced Tuesday that 31 athletes could be barred from the upcoming Rio de Janeiro Games after their samples from Beijing came back positive in retests.
The athletes have not been identified. The IOC says they come from 12 countries and competed in six sports.
IOC medical director Dr. Richard Budgett says in a conference call Wednesday that the athletes' "B'' samples will be analyzed in early June and the results available a few days later.
The IOC has also retested 250 samples from the 2012 London Olympics. Budgett says provisional results will be available within a week, with testing of the "B'' samples to take place "a couple of weeks later."
Budgett says athletes will be invited to be present for the testing of the "B'' samples.
If those tests also come back positive, the IOC can issue provisional suspensions. That would be followed by a disciplinary procedure that could bar athletes from Rio and strip them of their previous Olympic results, including any medals.
Budgett declined to say which substances were detected in the retests, but says the process involved improved methods for detecting steroids and EPO.
Budgett adds that a test for gene doping developed by Australian scientists could be ready for use at the Rio Games.
IOC President Thomas Bach says Brazil's new acting president has given him his personal commitment to deliver a successful Olympics in Rio de Janeiro.
Bach says he spoke by phone on Monday with Michel Temer, who took over as president last week after Dilma Rousseff was impeached by the Senate.
In addition to the political crisis, Brazil's economy is in deep recession and the country is in the grip of the Zika outbreak, with the games less than three months away.
Bach says Temer "was very clear in his personal commitment and that of his government to do everything to make these Olympic Games a great success."
He says Temer also invited to meet with him on his next visit to Brazil to discuss the Olympic preparations.
Bach says "from my side I expressed our full confidence in the success of these Olympic Games and the anticipation of being welcomed by the Brazilian people."
Russian Sports Minister Vitaly Mutko says the IOC has shown that doping is a problem not only for Russia and he proposes creating a single system "that will not allow for manipulation" and could be trusted around the world.
Speaking on Wednesday to the state news agency Tass, Mutkov said Russia was ready to help create such a system. He also said Russia was prepared to appoint a foreigner to head its anti-doping agency, where he said international specialists were already working.
Mutko said Russia was surprised by the reported U.S. investigation into allegations of state-sponsored doping and suggested the United States should stick to looking into its own national team, because "things are not so rosy there either."
IOC President Thomas Bach says Russian sports federations could be banned if allegations of state-sponsored doping at the 2014 Sochi Olympics are proven, but he declines to speculate whether Russia could be banned entirely from the upcoming games in Rio de Janeiro.
Bach tells reporters on a conference call that if the Sochi accusations are found to be true, sanctions could include "suspension or exclusion of entire national federations" - just as the IAAF suspended Russia's track and field federation from global competition.
Asked whether the Russian Olympic Committee itself could be suspended, Bach says: "I will not speculate because there comes a decision we have to make between collective responsibility and individual justice."
The IAAF will decide next month whether to keep or lift the ban on Russia's track team for the Rio Games.
Bach says the IOC wants "individual justice for the concerned athletes but also for the clean athletes around the globe."
He adds the IOC "will do everything to provide a level playing field ... and to protect the integrity of the competition" in Rio.
The IOC has no plans to open its own investigation into allegations of vote-buying tied to Tokyo's winning bid for the 2020 Olympics.
IOC President Thomas Bach says the Olympic body will remain a civil party to the ongoing investigation by French prosecutors. They are looking into a 2.8 million Singapore dollar ($2 million) payment from the Tokyo bid team to a Singapore account linked to the son of disgraced former IAAF President Lamine Diack.
Bach said in a conference call Wednesday: "We will not start a parallel inquiry. This could be hindering the legal procedures in France."
Bach said "we are not amused" about the allegations.
He said he IOC "took note" of a statement by Tokyo bid leaders acknowledging the payment but insisting it was for legitimate consulting fees.
Bach said the IOC has "all the instruments to fight against corruption." He added: "This does mean we are immune to corruption, but we do everything we can do address and fight this evil."
International Olympic Committee President Thomas Bach says he has no knowledge of a U.S. investigation into allegations of state-sponsored doping in Russia.
The New York Times reported that U.S. prosecutors are investigating claims that dozens of top Russian athletes participated in a sophisticated state-backed doping program. The probe was launched by the U.S. Attorney's office for the Eastern District of New York, the Times reported.
Bach says in a conference call Wednesday: "We have no information on this."
Pressed on the issue, he added: "I don't even know what it is. I don't know about any legal grounds for this. I don't know about the scope. I cannot comment on something I do not know."
The reported probe follows allegations by Russia's former anti-doping director, now living in the U.S., of an organized Russian doping scheme before and during the 2014 Winter Olympics in Sochi.
Asked whether he has been in contact with Russian President Vladimir Putin about the allegations, Bach said: "I have no communications whatsoever from the Kremlin."
IOC President Thomas Bach says anyone found to be involved in state-sponsored doping at the 2014 Sochi Olympics could receive a lifetime ban.
The International Olympic Committee has asked the World Anti-Doping Agency to carry out an investigation and plans to retest Sochi samples stored at the lab in Lausanne, Switzerland.
Bach says on a conference call that "if these allegations are proved we will hold everybody responsible who is implicated."
Bach says there would be "lifelong bans for any implicated person, not only athletes but anyone implicated," including national federations.
IOC President Thomas Bach says entire Russian sports federations could be suspended if allegations of state-supported doping at the 2014 Sochi Olympics are proven.
Bach says in an op-ed piece Wednesday that accusations that Russian officials subverted the drug-testing system at the Winter Games "represent a shocking new dimension in doping" and an "unimaginable level of criminality."
He says if the allegations are found to be true, sanctions could include lifetime Olympic bans, tough financial penalties and "suspension or exclusion of entire national federations" like the one already imposed by the IAAF on Russia's track and field program.
Bach's statement comes a day after the IOC announced that 31 athletes could be barred from this year's Olympics in Rio de Janeiro after their doping samples from the 2008 Beijing Games came back positive in retests.
IOC vice president John Coates says the most recent positive doping results from the 2008 Beijing Olympics proves "if we don't get you at the games, we will get you later."
In a major doping crackdown, 31 athletes in six sports could be barred from competing at the Rio de Janeiro Olympics in August after they were caught in retesting of samples from 2008.
The International Olympic Committee has opened disciplinary proceedings against the athletes from 12 countries who competed in Beijing and were planning to take part in Rio. The names and countries have not been published.
Coates, speaking in Sydney, said he was not aware if any of 31 were from Australia.
He says "I don't know where these athletes come from."
The president of the Japanese Olympic Committee says the body will investigate the 2020 bidding process and payments to a Singapore firm that has enmeshed the Tokyo bid in a bribery investigation.
Tsunekazu Takeda, who had been one of the leaders of the bid committee, told a parliamentary committee on Wednesday that people involved with the bid would be investigated.
Takeda says "we have decided to start an investigation into the matter, including questioning staff, to determine whether there was any illegality involved."
French prosecutors have said that 2.8 million Singapore dollars ($2 million) was apparently transferred from Japan to the Singapore account of a company called Black Tidings.
The account holder, Ian Tan Tong Han, has been closely tied to the son of former IAAF President Lamine Diack.
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