Credit: Patrick Semansky

Officials stand in front of a fire-damaged house in Baltimore, where an early morning fire claimed the lives of an adult and four children on Oct. 11, 2012.

An intense fire that ripped through a row house in northeast Baltimore early Thursday killed an adult and four children, a fire official said.

Fire department spokesman Chief Kevin Cartwright says firefighters were called around 2 a.m. and arrived to find heavy fire and smoke coming from the first and second floors of the home.

Cartwright said there were "intense flames coming out of every window and door in this structure."

Baltimore City Fire Chief James Clack told NBC affiliate WBALTV that 10 people were in home, and five escaped before the fire crews arrived.

One man jumped from a second-floor window to escape the blaze, he said. The man was taken to Johns Hopkins Bayview Medical Center for treatment, where he was in stable condition. Others, including a woman who handed a baby out of the home, escaped before firefighters arrived at the scene. Cartwright said he believes the baby is in good condition.

Firefighters found the bodies of five people during a search and rescue operation. The victims are believed to be a grandmother and her four grandchildren, Cartwright said. Their identities were not immediately released, but family members told NBC affiliate WBALTV at the scene that the children were 1, 3, 5 and 7. The woman who died was 55, they said.

Credit: Patrick Semansky

Barbara Hopkins, left, hugs her grandson, whose nickname was only given as Mick, outside of Hopkins' son's house in Baltimore on Oct. 11, 2012, after an early morning fire claimed the lives of an adult and four children.

Two firefighters were injured while battling the blaze when one fell through the second floor of the home into the basement. Both were taken to Bayview and were in stable condition.

The fire was brought under control around 3:45 a.m. Hours later, officials were still at the scene investigating while about 20 neighbors watched from a roped off area. The exterior of the two-story brick home was blackened by the fire, and wood beams in the roof were visible.

Fire investigators and police arson detectives told WBALTV were investigating what caused the blaze, but said they believed the fire may have started in the basement. 

Barbara Hopkins, who was standing outside the building, said her son had been in the fire and was being treated for third-degree burns at Bayview. She told WBALTV her son was the man who had jumped out the window and did so head first.

"He's severely burned," she said. "This is awful."

The Associated Press contributed to this report.

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