Maine State Fire Marshal John Dean is urging Mainers to check their smoke detectors in the wake of the fire deaths of two Searsport residents Monday whose smoke detectors inside their home were found without batteries.

"I'm convinced that a single working smoke detector would have saved both lives Monday in Searsport and the sad irony is that this house had three detectors -- all without batteries," Dean said in a statement.

"A properly installed and maintained smoke alarm in a house is one of the best and least expensive ways to provide a family with an early warning system of fire."

Dean praised the Searsport Fire Department which had gone door to door in the past two years handing out several hundred free smoke detectors, including on Porter Street, where the fire was.

Searsport officials do not think the home which burned Monday was a recipient of one of the free detectors because the house was already equipped with them.

The fire Monday morning took the lives on an 80-year-old man and his 28- year-old stepdaughter.

Both died from smoke inhalation.

"These fire deaths were preventable, if only a single battery had been in one of the three smoke detectors inside that home," Dean said.

"I urge Mainers to check their own smoke detectors to make sure each has a fully charged battery and that each detector is working."

Investigators say the fire started Monday from an overheated electrical power strip that had been covered with clothing.

Dean also urged Mainers to make sure power strips and extension cords are not covered by clothing and rug and are the proper size to handle the electrical load.