Groton – A Thames Street resident was displaced from his home on Friday following an early morning fire that damaged his apartment and was likely caused by an overloaded extension cord.

The City of Groton Fire Department was called out to a multi-family home at 189 Thames St. shortly after 2 a.m.

City Fire Chief Nicholas DeLia said the homeowner arrived home to his basement apartment with his son to find fire in the living room. The two initially tried to extinguish the flames by shoveling snow into the apartment.

The city department called on mutual aid from Electric Boat, the Naval Submarine Base and Poquonnock Bridge departments. One firefighter suffered a sprain while fighting the fire but did not seek medical treatment, DeLia said.

DeLia said it appears an overheated electrical cord was the cause of the fire. He said that anyone using extension cords should ensure that the cord is large enough to support the appliances that are plugged into it.

Red Cross volunteers also responded to the scene and is helping the homeowner with emergency food and clothing needs. Other apartments in the building were vacant.

DeLia said the apartment sustained moderate fire damage in the living room and heat damage throughout.