Fire crews battled a blaze at the RSU 20 bus garage on Prospect Street in Searsport on Saturday afternoon.
The Belfast Fire Department said it provided mutual aid to Searsport fire crews along with other departments, according to a social media post.
No one was injured and no buses were damaged in the fire, which was reported at about 3:30 p.m. Saturday, said WABI.
The cause of the fire remains under investigation.