Durham, N.C. — Police on Thursday identified a mother and son who were killed in a house fire over the weekend in Durham.

Wanda Roughton, 70, and Dean Davis, 48, died Saturday evening after flames erupted in their home at 120 Davidson Ave.

A preliminary investigation found that the fire likely started from a space heater in a rear bedroom.

The house did not have any working smoke detectors, authorities said.

Firefighters say smoke detectors and proper use of a space heater could have helped save the pair's lives.

Space heaters should be at least 3 feet from clothing or other flammable material, fire officials advise, and should be plugged directly into the wall, not an extension cord.

They also recommend smoke detectors on every floor of a home, outside every sleeping area and inside every bedroom.

Batteries should be replaced once every year.