About 250 people evacuated the two courthouse buildings in Westminster for 2 1/2 hours yesterday after a female caller told a District Court clerk, "There's a bomb in the courthouse."

No bomb was found, police said.

Investigators said the clerk received the phone call about 12:30 p.m. and notified the building security officers, who immediately sounded the fire alarm in the courthouse annex at 55 N. Court St.

The alarm sent about 200 employees, judges and other people in the several courtrooms into the cold weather.

A phone call to the old courthouse building also emptied that building.

Fire engines from Westminster, which were just returning from a fire in a house on Wesley Road, and an engine from Pleasant Valley, which had been filling in at the Westminster station, were dispatched to the bomb threat.

A bomb-sniffing dog from the Westminster police and two trained dogs from the state fire marshal's office checked both buildings. People were allowed to return at 2:55 p.m.

The annex building also contains offices of the Board of Education, which were checked by the dogs and their handlers.

The incident is being investigated, police said.