Camilla Smith smelled smoke and got her 14-year-old daughter and 4-year-old son out of the house, said firefighters, who were called at 1:32 a.m.

The fire started near the furnace and hot water heater in the basement and quickly spread upward, firefighters said.

A state police fire marshal has ruled the fire accidental, but planned to return today to try to determine a cause, firefighters said.

The two-story frame house is owned by Donald Pisegna of Farrell, said firefighters, adding that the house probably is repairable.

Ms. Smith and Pisegna did not have insurance.

The Smith family is being helped by the American Red Cross, who put them up in a local motel for the night, firefighters said.