CHARLOTTESVILLE, Va. » Rolling Stone cast doubt Friday on its story of a young woman who said she was gang-raped at a fraternity party at the University of Virginia, saying it has since learned of "discrepancies" in her account.

"Our trust in her was misplaced," the magazine’s editor, Will Dana, wrote in a signed apology.

The backpedaling dispirited advocates for rape victims who said they are concerned it could lead to a setback in efforts to combat sexual assaults both at U.Va. and college campuses elsewhere.

The lengthy article published last month focused on a woman it identified only as "Jackie," using her case as an example of what it called a culture of sexual violence hiding in plain sight at U.Va.

Rolling Stone said that because Jackie’s story was sensitive, the magazine honored her request not to contact the men who she claimed organized and participated in the attack. That prompted criticism from other news organizations.

"We were trying to be sensitive to the unfair shame and humiliation many women feel after a sexual assault and now regret the decision to not contact the alleged assaulters to get their account," the magazine’s statement said. "We are taking this seriously and apologize to anyone who was affected by the story."

The statement Rolling Stone posted on its website said discrepancies in the woman’s account became apparent "in the face of new information," but provided no details about what facts might be in question.

That wasn’t enough for some.

"It is deeply troubling that Rolling Stone magazine is now publicly walking away from its central storyline in its bombshell report on the University of Virginia without correcting what errors its editors believe were made," Attorney General Mark Herring said in a statement.

The original story noted that a dangerous mix of alcohol, date-rape drugs and forced sex at fraternity parties is by no means unique to any one U.S. university. In fact, U.Va. is one of 90 schools facing Title IX sexual-violence investigations from the Education Department, a list that includes four others in Virginia: the College of William and Mary; James Madison University; the University of Richmond; and Virginia Military Institute.

U.Va was roiled by the magazine’s initial article, which prompted protests, classroom debates, formal investigations and a suspension of fraternity activities.

Phi Kappa Psi, where the gang rape allegedly occurred on Sept. 28, 2012, was attacked after the article was published, with cinderblocks thrown through the fraternity house’s windows.

The main point of the article was that too many people at U.Va. put protecting the school’s image and their own reputations above seeking justice for sex crimes.

Over the past two weeks, the college community "has been more focused than ever" on preventing and responding to sexual violence on campus, U.Va. President Teresa Sullivan said in a statement.

"Today’s news must not alter this focus," Sullivan said. "We will continue to take a hard look at our practices, policies and procedures, and continue to dedicate ourselves to becoming a model institution in our educational programming, in the character of our student culture, and in our care for those who are victims."

Sullivan asked Charlottesville police to investigate the alleged gang rape. The police inquiry continued Friday.

Some state lawmakers proposed legislation requiring university officials to report sex assault allegations to the criminal justice system, rather than try to handle cases themselves. Another proposed requiring campus police to report assaults to local prosecutors within 48 hours.

The Phi Kappa Psi fraternity issued its own statement disputing the account of Jackie, who described being led upstairs by her date, who then allegedly orchestrated her gang-rape by seven men as he and another watched.

According to the Rolling Stone article, the woman said she recognized one attacker as a classmate, who reluctantly sodomized her with a bottle as others egged him on, saying, "Don’t you want to be a brother?"

The article said Jackie had met her date while they worked at the U.Va. pool, and that she quit her job as a lifeguard there to avoid seeing him thereafter.

But the fraternity said none of its members worked at the university’s Aquatic and Fitness Center in 2012, that it had no social event during the weekend when the woman said the rape took place, and that it doesn’t hold pledging parties until the fall.

"No ritualized sexual assault is part of our pledging or initiation process. This notion is vile, and we vehemently" dispute the claim, the fraternity statement said. "We continue to be shocked by the allegations and saddened by this story. We have no knowledge of these alleged acts being committed at our house or by our members. Anyone who commits any form of sexual assault, wherever or whenever, should be identified and brought to justice."

Two fourth-year students on campus said they were disappointed with how Rolling Stone treated Jackie, and said discrepancies in her story don’t mean what she said happened is untrue.

"I believe Jamie, period," said Greg Lewis, who added that he thinks U.Va. has an entrenched rape culture.

"At a certain point you have to say how many rapes is enough?" added Anna Boynton.

Some advocates expressed anger Friday that the magazine blamed the victim, rather than its own journalistic practices — and that efforts to prevent sexual violence could get waylaid as a result.

"It’s an advocate’s job to believe and support, never to play investigator or adjudicator," said Emily Renda, U.Va.’s project coordinator for sexual misconduct, policy and prevention, and a member of the governor’s Task Force on Combating Campus Sexual Violence.

Renda, who knows Jackie and also was interviewed for the Rolling Stone article, said, "I didn’t and don’t question Jackie’s credibility because that is not my role. Rolling Stone played adjudicator, investigator and advocate — and did a slipshod job at that."

Renda, a May graduate who said she was raped her freshman year at the school, added in an email that as a result of this, "Jackie suffers, the young men in Phi Kappa Psi suffered, and survivors everywhere can unfairly be called into question.

"We still have to build a culture of support and reporting so that justice can be done right and survivors can find healing.Rolling Stone has run roughshod over years of advocacy, over fairness and justice, and ultimately, over Jackie."

Even before Friday’s apology, some students said they found it hard to believe Jackie’s characterization of the response of her friends, who she said discouraged her from reporting the crime. "She’s gonna be the girl who cried ‘rape,’ and we’ll never be allowed into any frat party again," one friend said, according to the story.

"That was unbelievable," Devon Navon, a first-year student from Los Angeles, said last week. "Anyone I’ve met wouldn’t do that."

"I couldn’t comprehend that behavior," said Grant Fowler, a second-year student from Burke, Virginia. "No one I know would do that. I couldn’t understand how you could care so little about a person you call a friend."

Fowler said he found the story to be an exaggerated portrayal of the campus.

"The student body is not the Greek scene," he said last week. "The student body is supportive of victims. The student body is not as harsh as portrayed by the article."

Frommer reported from Washington. Associated Press Writer Greg Schreier in Atlanta contributed to this report.