A fire that damaged a home at 123 Amherst Street in Amherst originated from a fireplace, according to Amherst Fire Chief Mark Boynton.

Boynton said that radiant heat from the fireplace on the first floor caused the interior wall of to catch fire, and quickly spread undetected to the second floor and attic. 

The accidental two-alarm fire started around 5 a.m. Thursday morning and emergency crews were still on the scene later that morning. The top floor of the building sustained heavy damage from the flames.

Boynton said that two people were in the house when the fire started, but there were no injuries.

The Amherst Fire Department was joined by Milford, Mont Vernon, Merrimack, Bedford and Hollis crews on the scene.