SACRAMENTO, Calif. -- A fire damaged Cottage Elementary School in Sacramento early Thursday, but an official said arson is not suspected and classes will be held as usual.

Firefighters were called to the Morse Avenue campus at about 6 a.m. The flames damaged an office in the administration building.

The cause of the one-alarm blaze was not immediately known.

The school serves about 400 students. Students were not on campus at the time of the fire.

Trent Allen, spokesman for San Juan Unified School District, said students' medications stored in the school office were lost in the blaze. Students were being asked to bring backup medications.

The fire knocked out the school phone system. Allen said anyone needing to reach administrators should call the district at 916-971-7113.