BAINBRIDGE ISLAND, Wash. (AP) -- A fire that burned a shed on a fish pen in Puget Sound early Thursday was accidental.

Bainbridge Island Fire Department Assistant Chief Jared Moravec says investigators determined the fire at the American Gold Seafoods pen was started by the failure of a compressor used to aerate the water. Damage is estimated at about $20,000.

Moravec says the Coast Guard is working with the company in trying to clean up a spill of less than 100 gallons of diesel.

No one was at the pen when the fire was reported at 1:30 a.m. by the crew of a Bremerton ferry.

The fire had burned itself out by the time firefighters in a Coast Guard boat arrived at the pen several hundred yards off Bainbridge Island.

Copyright 2011 The AP.

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