The University of St. Thomas canceled classes Wednesday as campus security and St. Paul police investigated a bomb threat that was phoned in to the school.

An all-clear was pronounced just after 4 p.m. — more than six hours after two buildings off Summit Avenue were evacuated. The university received a threat targeting McNeely Hall, a building that houses classrooms and offices for the business school. Another nearby building where social work classes are held was also cleared.

“From language used by the caller it was apparent our public alerts were being monitored, so we began using alternate methods of communication,” university officials said. The FBI was immediately notified, but no suspicious objects were ever found.

Classes and all activities will resume Thursday morning.

The initial threat came via a call at 9:37 a.m., from someone claiming to have placed a bomb on campus, “but didn’t specify any particular location,” said university spokeswoman Vineeta Sawkar. Another call at 10:10 a.m. mentioned McNeely Hall and the buildings were evacuated, she said.

Classes campuswide were called off for the rest of the day and employees were sent home as authorities continued to search buildings, she said.

The school also advised parents coming to pick up students to go to McCarthy Gym west of Grand and Cretin avenues.

Children in a child care facility were moved to a location across Summit Avenue as a precaution, Sawkar said.

St. Paul police spokesman Sgt. Mike Ernster confirmed the threat and said officers were on campus to “make sure everybody is safe.”