A woman and her son escaped a fire early Saturday that heavily damaged their Pratt Street house, which firefighters said lacked working smoke detectors.

The woman called the town's Emergency Communications Center about 2 a.m. Saturday to report that her living room was ablaze. When firefighters arrived on the scene, the occupants had escaped the dwelling without injury, but fire and heavy smoke were billowing from the front of the structure.

While some of the fire crews doused the flames, others searched the building for any other residents or pets still inside.

Firefighters were able to control the fire quickly, according to the report, and flames were prevented from spreading the upper floors of the house. Engines 1, 2, 4 and 5, Ladders 1 and 2, and the shift commander were dispatched to the scene.

The woman and her 12-year-old son were evaluated at the scene by paramedics from AMR, but declined to be taken to a hospital for additional treatment.

In a statement issued after the fire, Assistant Fire Chief Scott Bisson said, "The lack of working smoke detectors allowed this fire to grow very large before the occupants realized the house was on fire and almost trapped them upstairs as they slept in their bedrooms.

"While the family lost all of their Christmas presents and decorations, they are very lucky to have escaped the blaze unharmed," he said.

The house was no longer habitable, firefighters said, and the woman and her son found alternate accommodations at a relative's home.

The cause of the fire is being investigated by the Fairfield fire marshal's office.