ROME (AP) -- Italian investigators have expanded their doping investigation into former Olympic race walk champion Alex Schwazer.
Authorities raided the offices of Italy's Olympic committee and athletics federation as part of a probe into what they suspect was a cover-up involving coaches and doctors.
Prosecutors in Schwazer's hometown of Bolzano on Wednesday named five people who have been placed under investigation in the case. They are Schwazer's former coach Michele Didoni, Italian athletics federation medical director Giuseppe Fischetto, federation physician Pierluigi Fiorella, federation secretary Rita Bottiglieri and equestrian athlete Karl Wechselberger.
The five are accused of being aware of Schwazer's doping before he tested positive and failing to report it.
On Tuesday, authorities raided the offices of Italy's Olympic committee and athletics federation as part of the Bolzano inquiry. Schwazer was banned by the Italian Olympic Committee for 3 1-2 years in April.
Schwazer, who won the 50-kilometer walk at the 2008 Beijing Games, was excluded from last year's London Olympics after testing positive for EPO before the games.
Prosecutors now believe coaches and physicians knew that Schwazer was doping long before he tested positive, possibly stretching back to Beijing.
"We need to follow this case and see if it involves merely allegations and controversy or well-founded accusations," Italy's Sports Minister Josefa Idem, a former Olympic canoe champion, said Wednesday. "In Italy we have a law that punishes not only those who practice doping but also those who aid and cover up those who practice it."
Schwazer failed an out-of-competition test before arriving in London and was removed from Italy's team before competing. He then admitted using the blood-boosting hormone EPO and said he was quitting the sport.
Schwazer has also admitted to consulting with Lance Armstrong's banned sports doctor Michele Ferrari. Schwazer maintains he was clean at the time of the Beijing Olympics.
He is being investigated by prosecutors in his hometown of Bolzano and in Padua, where an inquiry into banned physician Michele Ferrari is based. Rome prosecutors are also conducting an inquiry.
Italian financial daily Il Sole 24 printed alleged emails between Fiorella and Schwazer that appear to show knowledge of doping before the athlete was removed from Italy's team.
In a statement after the raids, the federation said that it offered judicial authorities full collaboration in the investigation.
The International Association of Athletics Federations denied that officials of the world governing body had evidence of Schwazer's doping but made no effort to stop him from competing in London. The allegations were contained in a New York Times report, which said the IAAF was aware of abnormal blood test results from April 2012.
"The IAAF is aware of and shocked by the accusations," it said in a statement. "The IAAF categorically refutes these claims in the strongest possible terms. The case outlined involved abnormal blood results with respect to an athlete's biological passport and was handled in strict accordance with IAAF rules and those of WADA."
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