it's possible.
Depends on the device used and how much explosive there was.
Of course if they weren't carrying one, that would negate it.
Must have been a pretty big bomb:
http://www.oudaily.com/vnews/display.v/ART/2005/10/02/433f3c43d0f24
4 p.m. — The FBI took over as the lead agency investigating the bombing Saturday during the OU football game against Kansas State. Three buses have been wiped down and sprayed, clearing the remains of the suicide bomber. The buses are still parked on the South Oval.