For university administrators, it is an alarmingly familiar story: A student's roommates find him to be sullen and uncommunicative. He writes violent stories in his English class that alarm his instructor. He is accused of harassing a female student.
Do campus officials see the pattern of behavior? And if they identify a student who poses a threat to others, what can they do? In short, the answer depends on the campus.
As universities across the nation deal with a surge in mental health problems among students, some campuses have taken an aggressive approach in how they monitor problem behavior and intervene in the lives of those who might pose a danger to themselves or others.
With counseling centers at many universities understaffed and swamped by requests for help, some schools urge students and faculty to be more active in reporting people who show signs of depression or aberrant behavior.
"What we've tried to establish is an early-warning system where we gather information about students who are in difficulty," said Michael Young, UC Santa Barbara vice chancellor for student affairs and co-chairman of a UC committee that examined mental health issues systemwide.
"It's proven from our point of view, the earlier you can identity a problem and respond appropriately, the better off the campus is," Young said.
At Virginia Tech, where student Seung-hui Cho killed 32 people and himself, officials saw warning signs as early as 2005.
That year, after Cho was accused of stalking two young women, he briefly was hospitalized for psychiatric evaluation. His roommates found him to be withdrawn.
Later, the violent plays he wrote for his creative writing class disturbed his fellow students and professor.
But for universities, putting such pieces together and knowing when a student is nearing a crisis can be a daunting task.
"You won't stop every suicide, you won't stop every homicide, but you can have a significant effect," Young said. "It's better to over-respond and overreact than to under-respond and under-react."
Young said UCSB, which has an enrollment of 20,000, collects information on troubled students from all over campus, creating a clearinghouse that allows officials to spot links between unusual activities or behaviors.
The campus expels several students a year who are deemed to pose a danger and tries to get them counseling, he said.
UCSB suffered its own tragedy in 2001 when student David Attias drove his car into a crowd of pedestrians in the student community of Isla Vista, killing four people. After the crash he raged that he was the "angel of death." A judge found him guilty of second-degree murder, ruled him insane and committed him indefinitely to a mental hospital.
At smaller universities, where students often have smaller classes, more contact with faculty and a more intimate setting, there is less chance of problems going unnoticed, officials say.
At Pepperdine University, which has about 4,000 students at its Malibu campus, administrators say there is a culture of students supporting one another.
"When someone faces difficulties or extraordinary challenges, it is likely more than one person will ask if they are OK," said Pepperdine spokesman Jerry Derloshon. "In the aftermath of the tragedy that took place at Virginia Tech, it has become obvious that it is important that we all try to help each other out."
At USC, which has about 27,000 students, administrators try to track students who have problems. Representatives of the counseling staff, campus police, residence halls and other branches meet each week to discuss student behavior and whether intervention might be needed in individual cases.
"We encourage students and faculty to bring forth things," said Bradford King, director of USC's student counseling service. "It's like Neighborhood Watch. What you hope is you have a community spirit where people are looking out for each other."
But how to balance the freewheeling ethos of college with the need for vigilance? Consider the dilemma posed by creative writing assignments. Cho's plays prompted Virginia Tech to pull him from an English class and give him private instruction.
Joseph Duemer, who teaches creative writing at Clarkson University in Potsdam, N.Y., expressed concern that universities might overreact to the Virginia Tech tragedy and inhibit creative freedom.
"One of the things you do when you teach the arts is encourage students to take aesthetic (& thus emotional) risks -- to extend themselves," he wrote in an online discussion on the Inside Higher Education website. "Sometimes this involves the sort of self-revelation that makes an instructor -- to say nothing of fellow students -- uncomfortable. But that freedom to explore is a fundamental part of the project; without it, we might as well not teach the arts."
The issue of whether artistic depictions of violence cross the line from healthy self-expression to pathological obsession also arises in high schools.