Lindeman's boyfriend, Clarence Myers, also lived in the home at 220 Old Route 40.
Lindeman was cut on the torso and legs, and Myers suffered smoke inhalation during a failed rescue attempt, the Fire Marshal's Office said in a news release.
Lindeman and Myers were taken to War Memorial Hospital in Berkeley Springs, W.Va., and later transferred to Winchester (Va.) Medical Center, Mowbray said.
A nurse at Winchester Medical Center declined Tuesday afternoon to release Lindeman's condition.
Myers was not listed as a patient at the Winchester hospital, a receptionist there said Tuesday afternoon.
The girls' bodies were to be taken to the Office of the Chief Medical Examiner in Baltimore for autopsies, Mowbray said.
Kevin Lewis, director of Fire and Emergency Services for Washington County, said the first units to arrive at the house went inside and tried to get to the second floor, where the girls were trapped, but were unsuccessful because of the intensity of the fire on the first floor.
The building became unsafe when an interior stairway was compromised and firefighters had to shift to a defensive posture, Lewis said.
The firefighters "displayed a lot of heroic efforts and options, but unfortunately, it did end up in the loss of two teenagers," he said.
Hancock Fire Chief Greg Yost and several Hancock firefighters were outside the burned-out home waiting for the opportunity to go back inside and complete their overhaul of the scene earlier Tuesday.
"It's been close to 20 years since we've had a fire like this in Hancock," said Yost, a veteran of the fire service there. "It's tragic. We made every effort to get in to those girls."
Yost said one firefighter's helmet was damaged by the extreme heat inside the home and the firefighter's face was affected by the high temperatures, but not enough to require medical attention.
Joseph G. Zurolo, deputy state fire marshal and spokesman, said Tuesday afternoon that investigators did not yet know why the girls weren't able to flee the burning house.
Lindeman told people that she heard smoke alarms go off in the house Monday night, but investigators could not immediately confirm that alarms sounded, Zurolo said.
Chris Shuman, who lives next door to the home, said he heard someone yelling at about 10:30 p.m. Monday.
As Shuman spoke Tuesday morning, investigators and a team of deputy state fire marshals walked in and out of what was left of his neighbors' home.
He said he twice heard the sound of a window shattering Monday night. Then he heard someone yelling and saw smoke at the home, he said. He called 911.
He saw Lindeman behind the house screaming "my babies, my babies," Shuman said. He did not know there were children in the home and said he thought Lindeman was referring to the family's dog.
Lindeman eventually was put on a stretcher and taken away in an ambulance, neighbors said.
When Shuman spotted the fire, he saw only smoke coming from the basement, but moments later, the house was fully engulfed, he said.
Shuman knew his neighbors only casually, noting they had lived next door for less than a year.
Another neighbor, who would not give his name, said Lindeman, her boyfriend and the girls lived in the home for seven or eight months.
The neighbor said he used to see the girls get off the school bus and run home.
"Two nice little girls," he said.
The girls were students at Hancock Middle-Senior High School, officials said.
Mowbray said Tuesday that officials were still in the early stages of the investigation. They were considering all possibilities in terms of what caused the fire, including whether it was accidental or arson, Mowbray said.
Investigators determined the fire originated in the basement, Mowbray said.
Washington County Assistant State's Attorney John Dunlap spent several hours at the scene Tuesday morning. The State's Attorney's office was assisting in the investigation, providing guidance, Mowbray said.
The right side of the house, where the girls' bedroom had been, was almost totally blackened, and the roof had partially collapsed. As firefighters and investigators worked inside the structure, their heads could be seen poking through the roof.
What was left of the front porch was standing but blackened, with what had been green paint still peeking through scorch marks.
The home appeared to be built of concrete blocks, and the brick facade had melted and peeled in the heat of the fire.
At about 10:30 a.m. Tuesday, a Hancock Rescue Squad ambulance pulled in front of the house. Firefighters using stretchers carried the two victims down a ladder from the second floor.
Fire officials estimated that the fire caused about $75,000 in damage to the structure and $15,000 in damage to its contents, Mowbray said.
Hancock police, Maryland State Police and the medical examiner's office were on the scene Tuesday morning.
Staff writers Marlo Barnhart and Heather Keels contributed to this story.
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