Concern about two suspicious packages mailed to Chancellor Larry Vanderhoef prompted a call to the regional bomb squad and caused the evacuation of Mrak Hall on Monday afternoon.

While about 300 Mrak Hall employees waited by the Mondavi Center more than a block away, bomb experts used a water cannon to detonate the packages. The small parcels turned out to contain a teddy bear, game and paperback book wrapped in Christmas paper and duct tape.

The packages generated concern because they bore a return address that matched the name of a person who has been sending what police say is "disturbing" e-mail to the chancellor in recent weeks, according to UC Davis Police Det. Sgt. Nader Oweis. Police are continuing to investigate the individual, who is not from the Davis area.

Police were called at 1:45 p.m. Tuesday when the chancellor's assistant received the packages through campus mail. Campus police then called the Sacramento-Yolo Regional Bomb Squad, who were unable to determine the contents of the packages due to their density. Initially, the fourth and fifth floors of Mrak Hall were evacuated, but the evacuation was extended to the entire building at 3:30 p.m. so that the items could be safely removed.

At about 4:30 p.m., the packages were blown apart with water and Mrak Hall was reopened.

Such an incident is unusual on campus. However, campus police encourage the UC Davis community to be constantly vigilant about reporting suspicious mail. Mail threats have been received in the past, including fake anthrax letters in fall 2001 and letters booby-trapped with razor blades in fall 1999.