"Up until Monday, the deadliest campus shooting in U.S. history took place in 1966 at the University of Texas, where Charles Whitman climbed to the 28th-floor observation deck of a clock tower and opened fire. He killed 16 people before he was gunned down by police. In the Columbine High bloodbath near Littleton, Colo., in 1999, two teenagers killed 12 fellow students and a teacher before taking their own lives."
from Yahoo's coverage
Police htat were loaned a civilian's rifle that someone on campus had.