COLUMBUS, Ohio -- In a sharply worded rebuke of Ohio State's Jim Tressel, the NCAA on Monday accused the 10-year coach of withholding information and lying to keep Buckeyes players on the field who had accepted improper benefits from the owner of a tattoo parlor.

In a "notice of allegations" sent to the school, the NCAA said Monday that the violations relating to the coach are considered "potential major violations."

Ohio State was not cited for the most serious of institutional breaches since Tressel hid information from his superiors for more than nine months. The university has 90 days to respond to the ruling body of college sports' request for information before a scheduled date before the NCAA's committee on infractions on Aug. 12 in Indianapolis.

In a 13-page indictment of Tressel's behavior, the NCAA alleged that Tressel had "permitted football student-athletes to participate in intercollegiate athletics while ineligible." It also said he "failed to deport himself ... [with] honesty and integrity" and said he was lying when he filled out a compliance form in September which said he had no knowledge of any NCAA violations by any of his players.

Tressel appeared at an awards banquet outside Cleveland on Monday night, ducking in out of the rain to shake hands with Cleveland Browns president Mike Holmgren before slipping into a side room. Tressel ignored reporters' questions about the NCAA allegations on his way to the ballroom before presenting a coaching award named for his late father, Lee Tressel.

While making the presentation, Tressel said, "There is nothing more important than the team and nothing more important than the kids."

Before the program ended, Tressel left the dais and was escorted out a side door and into a waiting car.

Athletic director Gene Smith said he would have "no comments until the case is resolved." The university issued a statement that the allegations were consistent with what it had already self-reported to the NCAA on March 8.

Tressel's troubles began with an April 2, 2010, email from Columbus lawyer Christopher Cicero. Cicero, a former Ohio State walk-on player, informed Tressel that a federal agency had raided the house of tattoo-shop owner Eddie Rife and discovered a multitude of autographed Ohio State jerseys, cleats, pants and helmets, Big Ten championship rings and the "gold pants" trinkets given to Buckeyes players for beating archrival Michigan.

Tressel responded, "I will get on it ASAP."

The NCAA says Ohio State's Jim Tressel "falsely attested" that he reported all knowledge of NCAA violations to the school. AP Photo/Terry Gilliam

Yet he did not notify Smith or Ohio State President E. Gordon Gee, anyone else in the athletic department, the NCAA compliance department, or anyone in the university's legal department. Instead, he forwarded the email to Jeannette, Pa., businessman Ted Sarniak, a friend and mentor to star quarterback Terrelle Pryor, who was subsequently discovered to be one of the players involved with Rife.

Tressel also called an FBI agent, according to The Columbus Dispatch, though the agent has said their eventual conversation wasn't concerning any potential NCAA violations.

Tressel's initial phone call to FBI Special Agent Harry Trombitas lasted less than a minute, according to documents obtained by the newspaper through a public-records request.

Trombitas' son, Matt, was a walk-on quarterback on the roster of Tressel's 2002 national championship team, the newspaper reported.

Trombitas returned Tressel's call on his cell phone the next morning, a call lasting five minutes, according to The Dispatch. Trombitas told the newspaper the call "wasn't related to anything like the situation that came out in the media."

Trombitas said Tressel was seeking information for a "friend of the coach or a former player who knew of a kid interested in [a career with] the FBI."

The newspaper reported that Tressel went on to exchange at least 12 emails with Cicero, and also had numerous lengthy telephone conversations with Sarniak over the weeks and months ahead. Tressel still did not tell any of his superiors, anyone at the NCAA or his own compliance or legal departments.

In September 2010, Tressel even signed a mandatory and rather routine Ohio State compliance form which clearly and simply asks if he the coach has knowledge of any NCAA violations. By signing and dating it, he said that he did not.

The U.S. Attorney contacted Ohio State in December to notify the university that it had come across the memorabilia. That prompted a cursory investigation -- Smith conceded to The Associated Press last week that the effort was rushed -- that did not turn up the telltale emails between Cicero and Tressel but did uncover the players' involvement with Rife. After consulting with the NCAA and the Big Ten, Pryor and four other top players were handed five-game suspensions -- curiously not including the next game, the Allstate Sugar Bowl, but beginning with the first five games of the 2011 season.