Authorities identified the victims as Christine Lehmann, 52, and her visiting son, Nicholas Lehmann, 25, who were pronounced dead at the scene. The fire broke out around 3:15 p.m. Sunday at 178 Fifty Acre Rd. South in the St. James section of Smithtown. The 91-year-old homeowner, Ronald Montagna, was hospitalized for smoke inhalation and burns. Roughly 80 firefighters from eight departments battled heavy flames for about two hours after reports of occupants trapped inside. Suffolk County Police arson and homicide detectives are investigating the cause, and tenants said the house operated as a rooming arrangement.