Kauai firefighters early Tuesday extinguished a fire that caused $30,000 damage to a storage shed at the Chicken in a Barrel restaurant in Kapaa.

Crews were dispatched to 4-1586 Kuhio Highway shortly before 1 a.m. and found the storage shed behind the restaurant involved in flames. The blaze was extinguished in 20 minutes. The cause is under investigation.

Damage to the structure and its contents, including the restaurant’s refrigeration unit and ice machine, was estimated at $30,000. A neighboring building also sustained some heat damage, officials said.