A University of Arizona student stormed a College of Nursing building on the Tucson campus in late October and shot and killed three professors before turning the gun on himself.

Armed with five guns and 200 rounds of ammunition, according to reports, 40-year-old Robert Flores fatally shot one instructor in an office before walking into a classroom during a midterm exam and killing two professors. He then ordered all the students out of the class and killed himself.

Flores, who was close to flunking out of the 380-student nursing school was reportedly plagued by academic and personal problems. Last year, two instructors at the nursing school contacted campus police to warn them that they viewed Flores as a threat.

The shooting closed much of the 34,000-student university, and left many students bewildered and frightened. Said a senior psychology major who was standing outside the building where the shooting took place: "You never think it is going to happen here."

A few weeks earlier at North Carolina State University, two graduate students were killed on campus in what police called a murder-suicide. The 31-year-old woman and 49-year-old man were found dead at an on-campus tennis court. At the scene, police found a gun and a note that indicated the pair knew each other.

The Raleigh campus has been the site of several serious crimes this academic year, including multiple robberies and an assault. Officials said they do not believe the murder-suicides is related to the crime.