Investigators collected evidence at the scene of the fatal fire. (Salwan Georges/The Washington Post)

A man and a woman were found dead Saturday morning inside a small house that burned in Southeast Washington, according to the D.C. fire department.

Authorities did not identify the victims. Both were found on the first floor of the single-story house in the 3300 block of Ely Place SE, according to Vito Maggiolo, a spokesman for the D.C. Fire and EMS Department.

Maggiolo said the victims “may have suffered injuries prior to the fire.” Investigators from the fire department and D.C. police were on the scene. A police spokeswoman said police are conducting a death investigation, but that the medical examiner will determine the cause of the victims’ deaths.

Firefighters were called to the house about 6:20 a.m. The department’s Twitter account described the dwelling as a wood frame house and said there was fire in the basement and on the first floor.

One firefighter fell through the first floor and was rescued. Maggiolo said the firefighter was not injured. The fire went to two alarms due to the firefighter’s “Mayday” call, and it was brought under control about 7:30 a.m.

The Humane Rescue Alliance took a large dog from the backyard of the house, the department said in a tweet Saturday morning.

A man and a woman were found dead early Saturday in the house fire on Ely Place SE. (D.C. Fire and Emergency Medical Services)

The house is located in the Greenway neighborhood, along the Anacostia Freeway and about halfway between East Capitol Street and Pennsylvania Avenue. On Saturday, it was surrounded by yellow police tape, with broken windows and a hole cut in the roof the only remnants of the fire.

Several neighbors said they didn’t know who lived in the home.

Maggiolo said that, around the same time, another smaller fire was reported in a house on D Street Southeast, around the corner from Ely Place. The spokesman said officials are trying to determine if the two fires are related.

Four people were displaced from the second fire and are being supported by the Red Cross, Maggiolo said. They were not injured, he said.

The fire scene (Salwan Georges/The Washington Post)