Newton firefighters responded to a three-alarm fire at a home on Hammond Street early Thursday morning. The home was a large, slate-roofed, single-family house in the Chestnut Hill area, said Lieutenant Eric Fricke, a spokesman for the Fire Department. Smoke alarms in the home woke the occupants in time for them to evacuate the house. No occupants or firefighters were injured, and the fire was knocked down in about a half-hour, Fricke said. The home sustained heavy smoke and water damage. The blaze is believed to have started in a second-floor bedroom, Fricke said. Fire investigators are looking into a possible cause.