The University of Virginia’s governing board unanimously approved a statement of “zero tolerance” of sexual assault Tuesday, less than a week after a magazine story detailed an alleged gang rape in 2012 at a university fraternity.

Leaders of the U-Va. board said they plan to meet again as early as mid-December to consider a plan of action from the university administration to address issues raised in a Nov. 19 Rolling Stone article that detailed allegations of a brutal sexual assault. The board also plans to draft a full statement on sexual assault in coming days and to make it public, leaders said.

Also Tuesday, Virginia Attorney General Mark R. Herring named the law firm O’Melveny & Myers as independent counsel to U-Va.’s Board of Visitors on ­sexual-violence issues. Among the lawyers involved in the assignment will be Walter Dellinger, a former acting U.S. solicitor general.

Herring said in a statement that he expects the lawyers to conduct an “aggressive and consequential” investigation of how U-Va. handled the alleged 2012 incident and other aspects of sexual violence.

The board, meeting for three hours in Charlottesville, heard from student leaders and activists, a faculty representative and the city police chief — all of whom expressed an urgent desire to change the culture of the university to prevent sexual assault.

University of Virginia students walk to campus past the Phi Kappa Psi fraternity house at the University of Virginia on Monday in Charlottesville. (Steve Helber/AP)

Appalled at revelations in the article, which portrayed an indifferent university response to the plight of assault victims, board members pledged strong reforms.

Some said the university faces a crisis. Board member L.D. Britt likened U-Va.’s predicament to what Penn State University confronted in the recent sexual-abuse scandal involving Jerry Sandusky, a former assistant football coach. Britt said U-Va. must shake up whatever is necessary to get the zero-tolerance message across.

“There will be no traditions deemed sacred if it puts our students in harm’s way,” Britt said.

Board member Helen Dragas grew tearful as she spoke. “Like so many of you, I have been heartbroken over the last several days,” she said, adding that the board must push hard to ensure major change. “No parent will ever fault us for micromanagement of their child’s safety.”

Board member Allison Cryor DiNardo said she couldn’t read the whole Rolling Stone article the first time she tried because she was too upset. “Full disclosure: It took me another day to finish the story,” she said. “I was just horrified."

Timothy Longo Sr., the Charlottesville police chief, pleaded for anyone who witnessed the 2012 incident at the heart of the article to contact authorities.

“We so much need people to come forward,” Longo said. The chief pounded his fist on the meeting table for emphasis, to send what he called “a clear message” on sexual assault: “Not on these grounds. Not now, not ever.”

Virginia’s flagship public university, which has about 23,000 students, has been abuzz since the article appeared online last week. It recounted the experience of a student — given an alias to shield her identity — who said she was gang-raped in her freshman year at the Phi Kappa Psi house. The student did not file a police report.

On Saturday, University President Teresa A. Sullivan suspended fraternity and sorority activities until Jan. 9 to give the community time to discuss the next steps. Sullivan also has called for any witnesses to the alleged rape to step forward to help authorities.

Much of the board meeting focused on connections between fraternities and sexual misconduct.

“Sexual violence is a problem in fraternities and the Greek system,” senior Tommy Reid, president of the Inter-Fraternity Council, told the board. “We don’t want to hide that. We need to change it. We need to confront it.”

Board member Bobbie G. Kilberg said the university should crack down on all underage drinking at fraternities. Brotherhood should not be defined by “alcohol bonding,” she said. “A ban, I think, is what really would make a difference.”

Reid replied that the university should be wary of any move that would push drinking “more and more underground.”