Pittsfield Fire Department tells us there was a structure fire on 11-13 Third Street just after midnight Saturday morning.

Authorities say upon arrival, they discovered a heavy fire on the exterior and left side of the building, going up into the attic space of the 2.5-story duplex.

They tell us all occupants of the building were evacuated and accounted for.

The fire department said the main body of the fire was put out within an hour.

Pittsfield Fire says there were no injuries, and all tenants were cleared to return to the building Saturday morning.

The fire is under investigation by the Pittsfield Fire Department Investigation Unit.