Durham District Attorney Mike Nifong has filed to drop charges of rape against three Duke men's lacrosse players who had been accused of attacking an exotic dancer at team party last year, a defense attorney said.

Charges of kidnapping and sexual offense against David Evans, Trinity '06, Collin Finnerty and Reade Seligmann remain. All three players have maintained their innocence throughout the case.

The charges of rape were dropped after the alleged victim told investigator Linwood Wilson Thursday that she could not say with certainty that penetration occurred with a male sex organ, Nifong wrote in the filing for dismissal. Because she could not testify to this matter, he wrote, the state could not reach the burden of proof for the charge of rape.

Defense attorney Joe Cheshire said "it's highly coincidental" that District Attorney Mike Nifong has decided to drop the rape charges a week after the director of a private DNA testing lab admitted in court that he had withheld test results displaying that the players' DNA was not found in the alleged victim's body or underwear.

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The Associated Press contributed to this story. Check www.dukechronicle.com for continuing news updates.