NORMAN, Okla. -- The University of Oklahoma will tighten security at Memorial Stadium after a student from Colorado with explosives attached to his body died in a blast within 100 yards of thousands of fans watching a football game there, the school's president said Tuesday.

Security personnel will more thoroughly search bags fans bring to the stadium, OU President David Boren said. The school will suspend for the rest of the season a policy that allows spectators to return after leaving at halftime, and officers will more closely screen vehicles that park in a garage next to the stadium.

"(Fans) should be prepared to come a little earlier and be patient with us, knowing that it's only for their own safety that we're being very, very thorough," Boren said.

Additional officers, both uniform and undercover, also will be scattered throughout the stadium.

"I would not be at all surprised that we would have more law enforcement agents inside the stadium than we would normally have," Boren said. "These will probably not be visible to the fans, because we probably won't be putting them in uniform."

Joel Henry Hinrichs III, 21, died Saturday when a device attached to his body exploded about 8 p.m. as he sat on a bench outside George Lynn Cross Hall, about 100 yards from the stadium. The blast could be heard inside the stadium where more than 80,000 people attended OU's game against Kansas State.

Boren said authorities continue to believe that Hinrichs did not try to get into the stadium.

Hinrichs' father, Joel Hinrichs, Jr., of Colorado Springs, Colo., said his son had battled several severe bouts of depression and had been going to counseling at a health center in Norman. He also described his son as a very private person. Hinricks, Jr. said he's confident his son didn't intend to harm others and wasn't motivated by a political agenda. He said no suicide note was found, but that the evidence points clearly to suicide.

Boren also confirmed that law enforcement officers found dangerous materials in Hinrichs' apartment on campus and detonated this material at the police bomb range.

The Oklahoma Sooners return to the stadium on Oct. 22 when they play Baylor. They play Texas in the Cotton Bowl in Dallas on Saturday.