New Haven firefighters put out a fire at a vacant four-story building, also known as the Winchester Building, in the downtown area.
Crews said they responded to the building at Science Park at 66 Hillside Place. The initial call came in at 8 p.m. and the fire was under control a little over an hour later.
Firefighters struck a second alarm for additional manpower.
Officials said the fire was located in the basement, which is unoccupied.
It is unknown if there are any injuries.