BALTIMORE — Fire engulfed a two-story row house yesterday, killing at least six people and injuring seven others, most of them members of an extended family, authorities said.Several victims were trapped inside the two-story brick row home and were burned so badly that firefighters had difficulty determining their ages and genders.

“The scene inside the house was something nobody should have to see, and nobody should have to die that way,” Fire Chief William J. Goodwin Jr. said.

The house was rented to a woman and her two sons, including one who used a wheelchair, the building owner said. Among the victims were a five-year-old boy who died on the way to the hospital and a three-year-old girl in critical condition.

The first firefighters to arrive found both floors engulfed in flames. They rescued three people, and three others managed to escape.

Goodwin said the heat from the fire was so intense that the victims died quickly. The cause remained under investigation yesterday afternoon, but foul play was not considered likely, authorities said.

Investigators believe the fire started on the first floor. There was no evidence the home had working smoke detectors, although fire department records show it had them in September 2005, Goodwin said.

Neighbour Helena Manning identified the family matriarch as Deneen Thomas, known as Neena. Thomas lived there with her daughter, two sons and two grandchildren, Manning said.

But she said she did not know why there were 13 people in the home when the fire started.

The building’s owner, O. Roosevelt Carlest, said he was aware that many people lived in the house. He said he had been trying to evict the family for not paying rent.

The home was in a low-income community of row houses near the historic Green Mount Cemetery, a city landmark.