COLLEYVILLE (CBSDFW.COM) – Fire investigators in Colleyville are still trying to determine what caused a fire than killed a teenager.

Flames broke out in the home in the 5700 block of Blue Quail Drive about one o’clock Tuesday morning. Fire officials said three people downstairs — a man, a woman, and a baby — escaped the flames. But a teenage female upstairs did not.

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Donny Penwell lives across the street. He said frantic knocking about 1 a.m. awakened his family. “Two or three of the girls and guys were just hollering, ‘The house is on fire, call 911!'” he told CBS 11 News.

Penwell said he could see flames on the front porch and kitchen, but it was the second floor that burned hardest.

“There was another boy, I don’t know who he was, but he was saying his daughter, I mean his sister was still upstairs,” according to Penwell, but she never exited the home.

It took firefighters from 6 mutual aid agencies 90 minutes to extinguish the blaze. Hours later they located the teen’s body on the second floor. By daylight, family members of those who stayed were sharing their grief and concern.

Communities such as Colleyville don’t suffer many fatal fires, so they are members of the Northeast Tarrant County Fire Investigation and Arson Task Force. They share investigative personnel to get to the bottom of fires like this, according to Colleyville Fire Marshall Robert McKeown. “Our office doesn’t have a lot of resources, so that is an avenue we can use to accomplish the goal,” he said.

Investigators don’t have a cause or even a firm location as to where the fire started. “We look at the structure as a whole and go from the least burned area to the most burned area to try to determine what the point of origin was,” said Marshal McKeown.

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Authorities aren’t releasing the names of any of the people in the house yet. The Tarrant County Medical Examiner hasn’t provided the identity of the fire victim, either.

The loss gave Donny Penwell pause. “You get to thinking how lucky you really are. It was horrible. It really was. You don’t wish that on anybody, for sure.”

(©2014 CBS Local Media, a division of CBS Radio Inc. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)

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