BERLIN -- German authorities said Tuesday they have received documents from doping expert Werner Franke that he claims show Tour de France winner Alberto Contador was involved in doping.
Franke said he has documents from last year's Operation Puerto doping investigation in Spain that show Contador, a Spaniard who won the doping-marred Tour on Sunday, had taken HMG-Lepori as a testosterone booster and an asthma product called TGN.
"We can confirm we have received the documents, and they will be incorporated into procedures of the district attorney's office," Christian Brockert, spokesman for Germany's Federal Criminal Police Office, told The Associated Press.
Brockert said the federal office will meet with the district attorney's office deemed to be responsible and assess the documents.
Contador, who rides for the Discovery Channel team, missed the 2006 Tour when his former team, Liberty, was disqualified because he and four other riders -- plus the team director and doctor -- were allegedly linked to Operation Puerto.
The Spanish doping investigation is one of the largest scandals in cycling history -- at least 50 riders are suspected of getting sophisticated drug services, including blood doping, from a Madrid clinic.
Contador said Saturday his name mistakenly turned up in the Puerto file.
"I was in the wrong team at the wrong time and somehow my name got among the documents," Contador said, adding cycling's governing body corrected the mistake.
He hasn't failed a doping test.
Franke, a molecular biologist, made his reputation by researching the systematic sports doping that turned the former East Germany into an Olympic powerhouse. He has clashed with Jan Ullrich, another rider linked to Operation Puerto.
A German court imposed a gag order on Franke for publicly naming how much the 1997 Tour winner paid the Madrid clinic, also based on documents from the investigation. It was believed there wasn't enough evidence establishing Ullrich, who has denied doping, as a customer.
But the case is headed back to court, because Ullrich's DNA samples since have been matched to blood bags seized at the Madrid clinic.
"They weren't doing that for free," Franke said.
He isn't the first to say he possesses copies of the Operation Puerto investigation in which Contador's name surfaces. France's Le Monde newspaper, along with several German ones, have printed parts of documents. More than a week ago, Germany's Bild and Suddeutsche Zeitung printed documents that purport to show the customers of the Madrid clinic.
The initials A.C. were listed, surrounded by other initials that matched up with Liberty riders.
Franke apparently has acquired other documents, saying only he got them "in my briefcase" while Spanish police weren't watching.
"I have the things in front of me; I can directly decipher them, what [drugs] were taken, because I also am in possession of the records of the house search of this Dr. Fuentes," Franke said.
Copies of the Operation Puerto investigation have surfaced so often in Germany that at one point a Web site -- unrelated to any legal body -- ran excerpts translated into German.
Doping allegations and suspicions have devastated the 2007 Tour. Three riders, including former overall leader Michael Rasmussen, and two teams were expelled during the three-week race. The International Cycling Union, however, considers the expulsions a sign the organization did its job.
"The 2007 Tour de France suffered greatly from doping problems," the UCI said in a statement Tuesday. "This was directly related to the significant increase in the number of anti-doping controls."