Germany's two-times Olympic cross-country skiing champion Evi Sachenbacher-Stehle and Italian police officer and four-man bobsledder William Frullani have been thrown out of the Olympics after testing positive for drugs.
Sachenbacher-Stehle, who was competing in the biathlon in Sochi but did not win a medal, tested positive for the stimulant methylhexanamin with the second "B" sample tested on Friday.
"The (German Olympic Committee) DOSB stands for a doping-free sport and a zero tolerance," German team chief Michael Vesper told reporters in Sochi.
"For us it is only clean performances that count. It is not an occasion I would have wished to experience."
Vesper said the athlete, who told him she must have taken the substance "inadvertently" through some nutritional supplement, was already on her way back to Germany.
"We had warned our athletes repeatedly of the dangers that these substances might have."
He said the IOC had yet to contact them following Friday's disciplinary commission meeting and had not announced their decision.
"I have not heard from them and I do not have their ruling," he said.
Sachenbacher-Stehle, provisionally banned for five days before the start of the Turin 2006 Olympics for high levels of haemoglobin in her blood, won gold in the team sprint at the 2010 Vancouver Olympics and in the 4x5km relay at the 2002 Salt Lake City Games.
The 33-year-old, who also has three Olympic cross country silvers to her name, narrowly missed out on medals in Sochi, coming fourth in both the 12.5km mass start and the mixed relay.
"I am currently living the worst nightmare I could ever imagine," she said in a brief statement.
"Because there is no way I can explain to myself how it could be that the sample tested positive."
She said she had given all her supplements to be tested prior to taking them or have the manufacturers guarantee they did not contain banned substances.
"The only thing I can assure everyone is that I did not take banned substances knowingly at any time and I will do everything to clarify this issue beyond doubt."
The athlete now faces a standard two-year ban as a first-time offender, a sanction that is decided by her international federation.
Frullani, a police officer by profession, was dropped from the team due to compete on Saturday after testing positive for the substance dymetylpentylamine, and left the village.
The substance is registered as a specified substance in the World Anti-Doping Agency (WADA) code which means he could potentially have taken it inadvertently and could face a smaller sanction than the two years.
The substance can also be found in nasal decongestants.
Italian team officials said they had been given a green light by the IOC to replace Frullani, a former decathlete who switched to bobsleigh in 2012, in their four-man team due to race on the last day of the Games.
"The Italian Olympic Committee (CONI) now needs to sort out the composition of the bobsleigh team which Frullani was part of, to make it back up to four," CONI said in a statement.
They have requested the athlete be replaced by the reserve Samuele Romanini and clearance for this has been received from the IOC.
The two cases mean the Sochi Games have had more positive tests than the Vancouver 2010 Olympics, where only one athlete was caught for using banned substances.
The IOC said before the Olympics it was planning to carry out 2,453 tests during the Games, including 1,269 pre-competition controls, which is a record for a Winter Olympics.
It has also increased pre-Olympic testing in the months leading up to the event so as to stop cheats from getting to the Games.
All Olympic medallists are tested as well as several other finalists, while hundreds more targeted tests are conducted based on intelligence.
Samples taken at the Sochi Olympics will be stored for a decade and re-tested in line with the new WADA Code that comes into effect on January 1, 2015.
Germany, who are fifth in the medals table with eight golds, sent a total of 154 athletes to Sochi. Italy, who have yet to win gold in Sochi, sent 114 athletes.
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