HAGERSTOWN, Md. (CBSDC/AP) — Two young sisters trapped by flames were found dead Friday in the ruins of their home near Myersville, authorities said.

Their father and another sister were hospitalized in Washington, and a firefighter injured in the blaze was in the hospital in nearby Frederick.

Madigan Lillard, 3, and Sophie Lillard, 6, were the only members of the six-member family still inside the house when fire and rescue units arrived at the Turkey Hill Estates subdivision late Thursday night, Frederick County Sheriff’s Cpl. Jennifer Bailey said. She said firefighters found the home engulfed when they arrived.

“Crews worked aggressively to locate the children, but their efforts were hampered by the volume of fire and unstable structure,” Bailey said in a statement.

State medical examiners determined that the girls died from smoke inhalation and ruled their deaths accidental, Bailey said.

Their father Jack Lillard, 39, was flown to MedStar Washington Hospital Center, she said. Officials there said they couldn’t discuss his condition.

Another daughter, 8-year-old Morgan, was taken to Children’s National Medical Center in Washington, Bailey said. A spokeswoman there didn’t immediately return a call regarding the girl’s condition.

The girls’ mother Angela Lillard, 33, and 7-month-old Sadie were treated at nearby Frederick Memorial Hospital and released, Bailey said.

She said a Middletown Volunteer Fire Company firefighter was also taken to Frederick Memorial for treatment.

Investigators were working to determine the cause of the blaze. They estimated property losses at $200,000.

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