An anonymous caller told police his roommate was headed to Yale University in New Haven, Conn., to shoot people, and witnesses spotted a man with a shotgun or rifle in the area, prompting Monday's campus shutdown, police said.
In a phone call that lasted only a few seconds, a male caller told a 911 operator that "his roommate was on his way to the university, to Yale University, to shoot people," said New Haven Police Department spokesman David Hartman in a televised news conference.
No shots or injuries have been reported as police swarmed the Ivy League campus, and Hartman could not confirm any arrests or detentions, nor provide a description of the suspect.
"We have reports that someone was seen with a long gun either on or near the campus," Hartman said.
Multiple SWAT teams were on the scene, police said, and investigators were also puzzling over the call, Hartman said.
"The call was cut short by the caller, so they didn't provide more information besides giving a statement of his roommate coming down," Hartman told reporters. "It was much more of a statement than a report to police. ... There was nothing specific about the threat."
The Ivy League university began its November recess Saturday, with classes scheduled to resume next week. Most students are away on break, according to Yale Alumni Magazine.
The campus repeatedly warned students of the lockdown and reports of a gunman on its website.
"Confirmed report of person with a gun on/near Old Campus. SHELTER IN PLACE. This is NOT a test," said one of the alerts.
When asked for an update on the lockdown, Yale's office of emergency management referred the Los Angeles Times to http://emergency.yale.edu/.