STATE COLLEGE, Pa. -- Penn State trustees fired football coach Joe Paterno and university president Graham Spanier amid the growing furor over how the school handled sex abuse allegations against a former assistant coach.

The massive shakeup Wednesday night came hours after Paterno announced that he planned to retire at the end of his 46th season, but the outcry following the arrest of former defensive coordinator Jerry Sandusky on molestation charges proved too much for the board to ignore.

"The university is much larger than its athletic teams," board vice chair John Surma said during a news conference. "The Penn State board of trustees tonight decided it is in the best interest of the university to have a change in leadership to deal with the difficult issues that we are facing."

Defensive coordinator Tom Bradley will be interim coach, and provost Rodney Erickson interim school president.

"The past several days have been absolutely terrible for the entire Penn State community," Surma said, "but the outrage that we feel is nothing compared to the physical and psychological suffering that allegedly took place."

Paterno said he was disappointed with the board's decision, but accepted it and urged everyone to remain calm and respect the school.

"A tragedy occurred, and we all have to have patience to let the legal process proceed," Paterno said in a statement late Wednesday night. "I appreciate the outpouring of support but want to emphasize that everyone should remain calm and please respect the university, its property and all that we value.

"I have been incredibly blessed to spend my entire career working with people I love. I am grateful beyond words to all of the coaches, players and staff who have been a part of this program. And to all of our fans and supporters, my family and I will be forever in your debt."

There was anything but a sense of calm on campus later Wednesday night. Police in riot gear dispersed about 2,000 students who took to the streets, crowds toppled a television news van and others kicked out its windows, and at least one photographer was pelted with a rock.

The students flooded downtown State College for about three hours. Officers used pepper spray at times to control the crowd. Some students chanted, "We want Joe! We want Joe!"

State College police said early Thursday they were still gathering information on any possible arrests.

Paterno received an envelope at his home Wednesday night 15 minutes before the board of trustees made its announcement, a source with first-hand knowledge told ESPN's Joe Schad. A note inside contained a phone number for Paterno to call. He did so and was told by one of two board members on the receiving end, "You are relieved of your duties."

According to the person close to Paterno, the coach had a hard time grasping what was contained in the allegations against Sandusky.

"I think the board took one look at the frenzy going on and the understandably horrific subject matter and said we can't have the focus on Joe for up to five more games," the source said.

Joe Paterno and his wife, Sue, stood outside their home and thanked Penn State students and supporters following Wednesday's firings. AP Photo/Gene J. Puskar

Joe Amendola, the attorney for Sandusky, told the The Patriot-News of Harrisburg, Pa., that Sandusky was "distraught and saddened" to hear that Paterno announced his retirement. The interview came before the board announced its decision to fire Paterno.

Sandusky maintains his innocence, Amendola added.

A key question throughout the scandal has been why Paterno and other top school officials didn't go to police in 2002 after being told by Mike McQueary, who is receivers coach now but was a graduate assistant at the time, that he had seen Sandusky assaulting a boy in a school shower.

A source told ESPN's Schad that Paterno hopes to clarify what he was told by McQueary as soon as Thursday. According to the source, Paterno recalls McQueary "vaguely" referencing "fondling" or "touching" or "horsing around" by Sandusky and a youth. But Paterno never had the understanding that McQueary had witnessed a "sodomy" or "rape."

Paterno has said he should have done more, while Spanier has said he was not told the details of the attack.

"Our great university has been rocked by serious charges against a former coach," Spanier said in a statement Wednesday night. "The presentment by the attorney general describes acts that should never be tolerated or ignored. I was stunned and outraged to learn that any predatory act might have occurred in a university facility or by someone associated with the university.