Updated at 7:28 p.m.: Revised to include the latest information.

A Baylor University graduate who says she was raped by football players in 2013 sued the university Friday. Her lawsuit includes an allegation that 31 Baylor football players committed at least 52 acts of rape, including five gang rapes, between 2011 and 2014 — an estimate that far exceeds the number previously provided by school officials.

Those figures could not be independently verified Friday, and Baylor officials declined to comment on their accuracy.

The woman, identified in the suit by the pseudonym Elizabeth Doe, reports being gang raped by then-Baylor football players Tre'Von Armstead and Shamycheal Chatman after a party on April 18, 2013.

Those football players were previously named as suspects in a sexual assault police report related to that date but were not charged. They could not be immediately reached for comment Friday.

The woman, a 2014 graduate of Baylor, is now suing the university for Title IX violations and negligence.

"Our hearts go out to any victims of sexual assault," interim university president David E. Garland said in a statement late Friday. "Any assault involving members of our campus community is reprehensible and inexcusable. Baylor University has taken unprecedented actions that have been well-documented in response to the issue of past and alleged sexual assaults involving our campus community."

John Clune, the Colorado attorney who represents the woman, said he appreciated what Baylor has done to try to fix its sexual assault problem, but "this is one that needed to be filed."

"As hard as the events at Baylor have been for people to hear, what went on there was much worse than has been reported," he said in a statement.

One of the woman's alleged attackers — Chatman — was accused of rape once before, the suit says, but the university failed to intervene. In that case, the suit says, a student athletic trainer reported that Chatman raped her at his off-campus apartment, so the university moved the trainer to a female sports team and agreed to pay for her education in exchange for a non-disclosure agreement.

'Show 'em a good time'

The lawsuit describes a culture of sexual violence under former Baylor football coach Art Briles in which the school implemented a "show 'em a good time" policy that "used sex to sell" the football program to recruits. That included escorting underage recruits to strip clubs and arranging women to have sex with prospective players, the suit alleges.

Former assistant coach Kendal Briles — the son of the head coach — once told a Dallas-area student athlete, "Do you like white women? Because we have a lot of them at Baylor and they love football players," according to the suit.

An "It's On Us" campaign sign was placed across Martin Residence Hall on the Baylor University campus in Waco on May 3, 2016.

Investigation by lawyers identified at least 52 "acts of rape," including five gang rapes, by 31 football players in a four-year period. At least two of the gang rapes were committed by 10 or more players at one time, the suit states.

This contrasts with figures Baylor officials have provided based on an investigation by Pennsylvania-based law firm Pepper Hamilton, which looked into how Baylor handled sexual assault on campus. Regents told The Wall Street Journal in October that they were aware of 17 women who reported sexual or domestic assaults involving 19 players, including four alleged gang rapes, since 2011.

Tonya Lewis, a Baylor spokeswoman, declined to answer specific questions about Baylor's knowledge of the prior alleged sexual assault by Chatman or the alleged non-disclosure agreement. She also declined to comment on the scope of the Pepper Hamilton investigation or whether the university stands by the numbers it originally provided.

Clune, who has represented four Baylor survivors, including two who received settlements with the university, defended the thoroughness of his investigation.

"We have no idea how the regents came up with their numbers, but they do not represent the total number of assaults," he said. "I'm not sure that was Pepper's assignment either."

Art Briles' response

Art Briles, the former head football coach who was fired in May in response to the scandal, had no knowledge of the 52 sexual assaults cited in the lawsuit, or of any payoff to a victim to keep quiet, his lawyer Ernest Cannon said.

"Lawyers can say whatever they want to in pleadings," Cannon said. "I haven't seen any facts."

He added that the quote in the lawsuit attributed to his client's son, Kendal Briles, did not "sound like the Kendal that I know." Florida Atlantic University, which recently hired Kendal Briles to be its offensive coordinator, did not respond for a request for comment.

The allegations also were met with push back by a former recruiting chair for the Baylor Bruins, a "hostess" group for prospective athletes visiting campus. Katie Norman tweeted that no one in the Baylor Bruins instructed women to sleep with recruits, and that she was only asked to hang out with them at games.

I'm not sure if someone outside our organization told someone to sleep with a recruit, but no one in Baylor Bruins ever told someone to. — Katie Norman (@callme_norm) January 28, 2017

Lawsuit's allegations

The lawsuit says that Doe originally applied to Baylor, the world's largest Baptist university, because of its Christian-centered approach to education. She enrolled in 2010, with the intention to pursue a degree in medicine and in 2012 joined the Baylor Bruins.

On April 18, 2013, according to the lawsuit, Doe attended a party at the home of former Baylor defensive end Shawn Oakman, who has since been charged with sexual assault in an unrelated incident.

Doe became intoxicated at the party and apparently returned home with Armstead and Chatman. When her roommate's boyfriend arrived later that night, the suit says, he heard "what sounded like wrestling and a fist hitting someone," a loud bang and a woman saying "no."

When the boyfriend asked if everything was OK, one of the men inside yelled that Doe "was fine." Armstead and Chatman then emerged from the room, and the boyfriend saw Doe partially unclothed on the floor. The woman had a bruise on her cheek and a bite mark on her neck, according to the suit.

Doe initially told police she had not been sexually assaulted but later decided to file a report because she woke up with bruises and a feeling in her vaginal area that indicated she had had sex, even though she did not remember.

One of the woman's teammates on the Baylor Bruin group to host prospective athletes instructed Doe to tell police she had "consensual sex with one white male" to protect the athletes, the lawsuit alleges. It cites a Title IX investigation into the incident, which later showed that Chatman had called the Bruin and given her the "assignment."

Doe made a complaint to the Waco Police Department but declined to press charges, records show.

No Baylor investigation

Baylor did not investigate — as required by Title IX, the federal law that instructs universities to proactively protect students from sexual violence and hostility — for more than two years, according to the lawsuit and a report by ESPN.

Meanwhile, Chatman transferred to Sam Houston State, but Armstead remained on campus. The lawsuit states that Doe "walked onto campus in daily fear of running into her rapist and in fact did just that on repeat occasions."

In the fall of 2015, Baylor's newly created Title IX office investigated the woman's complaint. Armstead was dismissed around the same time for a "team rules violation." He was eventually found responsible for the rape and expelled last spring, the lawsuit says.

Armstead has maintained that he did not have sex with the woman, ESPN's Outside The Lines reported in April. The show also reported that Chatman told Baylor officials that the men did have sex with her.

Lewis, the university spokeswoman, confirmed that Armstead and Chatman are no longer enrolled at the university.