WASHINGTON: A series of bomb threats and other security alerts rattled US schools and universities as nerves remained frayed from the massacre of 32 people by a disturbed, brooding student at Virginia Tech.
With the Virginia Tech campus still on edge, students there got another scare when police swarmed into a building housing the university president's office. An initial report of suspicious activity turned out to be a false alarm.
The campus remains in shock after after the bloodiest shooting spree in modern US history.
In central San Francisco, the University of California Hastings College of the Law evacuated 300 to 400 students midway through classes after someone noticed a posting on an Internet site referring to the school and Virginia Tech, Dean Nell Jessup Newton said.
"Somebody who read that bulletin board called us. You could read it as sort of a sick joke or you could read it as something that was serious," she said. "We called the police and the FBI and they are investigating, but in light of the Virginia Tech situation we decided in a kind of excess of caution to close down the school for the rest of the day."
At the University of Minnesota in Minneapolis, eight buildings were evacuated after a bomb threat, the school said.
Classes in the buildings were cancelled for the rest of the day and students were asked to return to residence halls and not congregate in the area, the university said.
A high school and a middle school in Columbia, Missouri, were locked down on after gunfire was exchanged between two cars nearby, and two people were taken into custody, the Columbia Tribune reported.
The University of Missouri said in a notice on its website the shooting did not take place on its campus.
At Vista Murrieta High School in Murrieta, 80km south of Los Angeles, graffiti threatening that everyone would die on April 20 - the anniversary of the Columbine shootings - and that bombs had been planted was found on Wednesday.
Security was beefed up, local media reported.
San Diego State University received an apparently bogus threat overnight to carry out a Virginia Tech-style killing spree. Staff alerted police and a suspect was being questioned but campus activities continued as normal.
In the Denver area, three schools received threats against specific students or of bomb threats. One was locked down briefly, one briefly evacuated and another was put on security alert. Nothing was found in any case, The Denver Post reported.
An 18-year-old student at the Lawrenceville School, a boarding school for high school students in Lawrenceville, New Jersey, was taken into custody by police on Wednesday afternoon after he waved an air gun out of a dormitory window.
