A four-month police investigation into an alleged gang rape at the University of Virginia that Rolling Stone magazine described in graphic detail produced no evidence of the attack and was handicapped by the accuser's unwillingness to cooperate, authorities said. The magazine article, titled A Rape On Campus , sparked a national conversation about sexual assaults at American universities after it was published last November. The article focused on a student identified only as 'Jackie' who said she was raped at the Phi Kappa Psi fraternity more than two years earlier. It described a hidden culture of sexual violence fuelled by binge drinking at the college. Police said they found no evidence of that either. There were numerous discrepancies between the article and what investigators found, Charlottesville Police Chief Timothy Longo announced on Monday, taking care not to accuse Jackie of lying. The case is suspended, not closed, and the fact that investigators could not find evidence years later "doesn't mean that something terrible didn't happen to Jackie," Longo said. He appealed for anyone with information about any sexual violence to immediately alert police, and expressed hope that Jackie may one day feel comfortable explaining what really happened. Asked if Jackie would be charged with making a false report, he said: "Absolutely not." Jackie's attorney, Palma Pustilnik, said she would have no comment on the investigation. The article heightened scrutiny of campus sexual assaults amid a campaign by President Barack Obama to end them. The University of Virginia had already been on the Department of Education's list of 55 colleges under investigation for their handling of sex assault violations.