Officials said the students had been "separated from TCU" and criminally barred from campus, but it wasn't clear if the players had been kicked off the team. But their names had already been removed from the football roster posted on the school's athletic website.
"I expect our student-athletes to serve as ambassadors for the university and will not tolerate behavior that reflects poorly on TCU, the athletics department, our teams or other student-athletes within the department," athletic director Chris Del Conte said. "Our student-athletes are a microcosm of society and unfortunately that means some of our players reflect a culture that glorifies drugs and drug use. That mindset is not reflected by TCU nor will it be allowed within athletics."
Brock was the leading tackler for TCU as a sophomore during the 2010 season, when the Horned Frogs went 13-0, won the Rose Bowl and finished the year ranked No. 2. Brock started the season opener at Baylor last September, but aggravated a foot injury that required season-ending surgery.
Yendrey started 12 of 13 games this past season, when he had 39 tackles and three sacks. Johnson played in all 13 games, starting the last eight, and had 47 tackles with 2 1/2 sacks.
Brock likely would have been a starter again in 2012. Yendrey, who also started five guys as a junior, and Johnson both were juniors last season and had another season of eligibility. Horn appeared in 10 games this past season, making one start. He played in eight games as a freshman.
"Under my watch, drugs and drug use by TCU's student-athletes will not be tolerated by me or any member of my coaching staff," Patterson said. "I believe strongly that young people's lives are more important than wins or losses.
He added: "At the end of the day, though, sometimes young people make poor choices. The Horned Frogs are bigger and stronger than those involved."
Boschini, the chancellor, called the charges against all the students "simply unacceptable." Fraternity members were among those arrested, though Boschini said he didn't think any whole fraternity houses were at fault.
"Today's events have changed the life of everybody at TCU," Boschini said.
AP Sports Writer Stephen Hawkins contributed to this report.
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