Fire destroyed an office behind Morihara Store on Maui this morning in Kula.

Firefighters responding to an alarm at 3:09 a.m. found the 700 square foot office on 4581 Lower Kula Road behind Morihara store ablaze.

The office was empty at the time.

Firefighters brought the blaze under control 30 minutes later and extinguished by 6:50 a.m.

Damage is estimated at $147,000 to the building, $12,000 to its contents and $1,000 to the wall of Morihara Store.

Investigators have not determined what started the fire, but said its origin is "suspicious."