GARDINER — Fire damaged a Highland Avenue duplex apartment building Monday night, displacing the building’s only tenant.

The fire at 12 Highland Ave. was reported around 11:30 p.m. and was extinguished by firefighters from seven area fire departments.

The fire started on the second floor, which was vacant. The second floor sustained significant damage, according to Fire Chief Al Nelson.

The building’s only tenant, who lives on the first floor, was at work at the time of the fire. The first floor sustained water and smoke damage. Nelson said that tenant was staying with her family.

An investigator with the Office of the State Fire Marshal was at the fire scene and was expected to return Tuesday to determine a cause of the fire. So far, Nelson said, the cause is undetermined.

Nelson said the building is owned by David F. Dineen Jr. However, city assessing records indicate the home was owned by Dineen from 1998 to 2014. In October 2014, the listed owner was changed to the city of Gardiner. And in November 2014, the listed owner was changed again, to Bank of Maine, which was later purchased by Camden National Bank, which is listed as the current owner on city records.

The blue building with white trim was built in 1860 and is assessed, for tax purposes, at $77,800.

Nelson said rebuilding the second floor might be possible and, eventually, reoccupying the building might be possible. However, he noted the electricity to the building has been cut off because of the fire damage.

Firefighters from Gardiner, West Gardiner, Augusta, Togus, Pittston, Randolph and Farmingdale responded to the emergency call. They were at the scene until around 2 a.m. Tuesday.

Nelson said the building’s second story was “well involved” when firefighters arrived.

“It all went pretty well. The guys did a great job knocking down the fire and preventing further damage,” Nelson said.

Nelson said firefighters reported they heard smoke detectors emitting warning sounds when they arrived at the fire scene.

The fire was reported by a passer-by.

Keith Edwards — 621-5647

[email protected]

Twitter: @kedwardskj