University spokesperson Martin M. Mbugua declined to comment Tuesday on the ongoing investigation into the bomb threat that closed the Princeton University campus last week.

The University evacuated staff and students on June 11 after receiving a “credible” bomb threat for multiple, unspecified campus buildings.

The person who called in the bomb threat has not yet been caught. Mr. Mbugua said that there have been no arrests and that the Princeton University’s Department of Public Safety is in charge of the investigation along with other law enforcement agencies, including the FBI.

Asked about rumors that the caller had given details about the ingredients used in the bomb, Mr. Mbugua said that he was unable to provide any details as to what made the threat credible. “That is determined by the Department of Public Safety,” he said “and since this is an ongoing investigation I cannot discuss specifics of how the credibility of the threat was determined.”

Some 6,900 people were evacuated from campus and off-campus buildings after the threat was received at 8:57 a.m. and the University started sending out e-mail alerts at 10:30 a.m. Washington Road and North Harrison Street were closed to traffic coming from Route 1 around 11:40 a.m. and reopened around 12:30 p.m. Princeton’s Dinky train closed for an hour starting at 11:45 a.m. and the University’s TigerTransit service was suspended until Wednesday, June 12. Bomb-sniffing dogs were called in to look for explosives but found none and the campus was reopened at 6:25 p.m.

As a precautionary measure Superintendent of Schools Judy Wilson prohibited outside student activity for the day and all after school activities were canceled.

Shortly after the threat was called in, authorities checked out a suspicious package found at the Lawrence Road Apartments off Alexander Street. The apartment complex houses University graduate students. The item was discovered to be a harmless kitchen item left by someone moving out of the apartment complex.

A number of local, county, state and federal agencies took part in the response. In addition to the University’s Department of Public Safety and the Princeton Police Department, responders included the FBI, New Jersey Transit Police, the Bureau of Alcohol, Tobacco, Firearms, and Explosives, state Police, the Mercer County Prosecutor’s Office and Sheriff’s Office, the Monmouth County K-9 unit, and Princeton First Aid and Rescue.

Friday’s False Alarm

On Friday, June 14, a member of the U.S. Marshals Service walking near the entrance of the Nassau Inn noticed an unattended bag near a structural support to the building. He reported the item a 5:43 p.m. and Princeton Police Department responded.

According to Captain Nick Sutter, no one had been seen leaving the item and no owner could be found. The item had been left unattended for over an hour. Access to the immediate area was restricted as surveillance footage was checked. The footage did not reveal who left the bag or when.

A canine unit from the New Jersey State Police (NJSP) was called in and in consultation with NJSP investigators raised the level of the package from unattended to suspicious. NJSP then requested explosive technicians and Palmer Square East was closed to vehicular and pedestrian traffic at 6:18 p.m.

The bomb squad arrived around 7 p.m. and, after examining the package from a distance, ordered an immediate and full evacuation of all Palmer Square East buildings including restaurants, stores and the Nassau Inn before examining the package at closer quarters.

The evacuation, which was done in conjunction with Palmer Square Management and the management staff of the Nassau Inn, was completed by 7:30 p.m. and by 8:22 p.m. the bag was deemed safe. The ‘all clear’ was given and the area was reopened. The bag belongs to a customer at the Nassau Inn who has since been found and contacted, said Mr. Sutter.