PORTLAND — Fires at a waterfront warehouse in Portland, an auto body shop in East Vassalboro and at Camp Sebago kept firefighters and investigators busy this week.

A fire at a warehouse on Portland’s waterfront Thursday may have been sparked by exhaust fumes from a lift truck catching paper inside on fire, a company official said.

The fire broke out at the warehouse at Merrill’s Marine Terminal at about 3 a.m., said firefighters, who battled it from land and from the water.

About a half-dozen workers were at the warehouse, which held about 500 tons of recycled paper, but firefighters said no one was hurt. They said the building likely can be repaired.

Firefighters from four towns combated a fire that broke out in an East Vassalboro auto body shop around 7:30 p.m. Wednesday.

The owners of Freddie’s Service Center believed the fire started in or near the chimney. They said the building had extensive damage.

Authorities believed an improperly installed wood stove sparked a fire that destroyed a garage at Camp Sebago on Tuesday.

The fire at the Salvation Army camp caused $400,000 in damage. It took six hours for firefighters from five towns to put out the blaze.