The fire broke out at the yacht club marina, located on 500 Artisan Way in Assembly Row, in Somerville, around 5:20 p.m. on Wednesday, March 22, according to the Somerville Fire Department.
One commuter was able to see the blaze while traveling on the Orange Line.
The fire fully involved the cabin cruiser style vessel.
"The fire was contained to the single vessel thanks to an aggressive attack from the dock using hand lines and by our marine unit partners from the water," the Somerville Fire Department said in a Facebook post.
Firefighters from Boston, Cambridge, and Medford provided mutual aid to extinguish the flames.
No injuries were reported from the incident, which was cleared by 6:45 p.m., the Somerville Fire Department told Daily Voice.
The cause of the fire remains under investigation.
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