A crew member was using a welding torch below deck near the ship's stern when he accidentally ignited a fuel line just after 6 p.m., according to Kyle Moore of the Seattle Fire Department.
Crew members were able to seal off the area and get above deck, and firefighters arrived moments later and flooded the area. A vacuum truck then sucked out all the water and fuel, Moore said.
None of the ship's eight crew members were injured in the fire. It's unclear how much damage was done to the ship.