ANCHORAGE, Alaska — A 63-foot U.S. Fish and Wildlife Service boat sank as it was docked in Kodiak.

The Coast Guard says the research vessel Arlluk was discovered submerged by harbormaster staff at 3:30 a.m. Friday.

The cause is not known.

No one was on board at the time and no injuries were reported.

A contractor worked during the day to plug openings and refloat the vessel.

Fish and Wildlife Service spokesman Bruce Woods says no more than 10 gallons of diesel fuel spilled into St. Herman's Harbor.

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