A list of campus shootings from the Associated Press includes one I hadn't heard of:

A list of deadly U.S. campus shootings - International Herald Tribune

Nov. 1, 1991: Gang Lu, 28, a graduate student in physics from China, reportedly upset because he was passed over for an academic honor, opens fire in two buildings on the University of Iowa campus. Five university employees are killed, including four members of the physics department; one other person is wounded. The student fatally shoots himself.

Worth reading on this story:

Surviving the Graduate Curriculum

ADALAIDE MORRIS

While no one publicly endorsed Gang Lu’s remedies, his complaints set cracked bells clanging all across campus. Police in plainclothes hung out in department offices where threats had been made; a student who told a slow clerk that she too should have been shot was severely reprimanded; another student was deported. Then, one supper time in early December, I got a call warning me that an English department graduate student—a student whose comprehensive examination lists I had questioned three weeks before—was saying that I should be “stopped,” I should “learn a lesson from Gang Lu,” I should know that Gang Lu’s victims owed him a debt and had, by now, forgiven him. In mid-November this student had been committed to an inpatient psychiatric unit, but in December, having convinced a judge that her threats were “only poetry,” she was released. With the murder of five of my colleagues fresh in my mind, I was—I confess—terrified. “But why,” I asked a graduate student who was recounting one of my would-be assassin’s more sustained tirades, “why didn’t you interrupt her?” “Because you,” the student replied, hesitantly, as if hearing her words, too, from the outside, “have more power than she does?”[More]

Reading the essay, I think Professor Morris still believes in the "hierarchies of race, gender, and class " that modern educators spend so much time on, but you can see this gave her a pause.