SEATTLE, WA - The Seattle fire department is blaming "improperly discarded staining rags" for starting a fire at a Ballard boat house, which lead to the destruction of up to five boats, including two antique vessels. The rags, which were soaked in a oil staining product, spontaneously burst into flames inside the covered boat storage structure.

The fire broke out just before 8 p.m. at the boat house along the 5100 block of Shilshole Avenue Northwest, which is just east of the Chittenden locks along Salmon Bay. The fire sent thick plumes of black smoke into the sky over Ballard, which could be seen for miles around. As the fire burned, explosions could be heard coming from the structure. One boater captured an explosion on camera:

Joshua Browne was just pulling into Shilshole Marina this evening when he saw this. @SeattleFire on scene. #komonews pic.twitter.com/UVwpcZyqdu

— Kendra Gilbert (@KLGnews) May 22, 2017

Seattle firefighters attacked the fire from the water, and then land-based firefighters entered the boat house to put out spot fires. Firefighters were at the scene past midnight monitoring the structure.