Washington (CNN) -- Former U.S. Rep. Gary Condit's semen was found on underwear belonging to Chandra Levy, according to an FBI biologist testifying Wednesday in the trial of Ingmar Guandique, who is accused of murdering the Washington intern in 2001. The panties were retrieved in May 2001 by investigators searching Levy's apartment in the days after her parents reported her missing. Her body was found over a year later in Washington's Rock Creek Park. The testimony addresses the question of whether Condit, a sitting congressman from California at the time Levy vanished, was having an affair with the intern, who had just turned 24 when she disappeared.
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NEW:Prosecutors have recommended dropping 2 of the six charges against Guandique
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Ingmar Guandique is accused of murdering Levy while she was jogging
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Former Rep. Gary Condit's semen was found on Chandra Levy's underwear, FBI says
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Condit has refused to state that he was having an affair with Levy
The congressman was never a suspect in the case, but was questioned intensively for details as to @placeholder's whereabouts.