OKLAHOMA CITY (AP) -- A house fire Friday morning killed a man and his two daughters and injured two people, including a firefighter, officials said.

The names and ages of the victims were not immediately released.

The mother escaped the flames through a broken window with the help of neighbors and was hospitalized. Her condition was not released.

A firefighter suffered severe back spasms and was treated and released at a local hospital, Deputy Fire Chief Cecil Clay said.

The fire was reported at 2:38 a.m. and the home was engulfed in flames with heavy smoke pouring from doors and windows when firefighters arrived, Clay said.

When firefighters learned people were still inside the burning house they went in through a window to try for a rescue. They were able to bring the two girls outside, but were unable to revive them.

The man's body could not be recovered until the fire was put out.

The cause of the fire was still under investigation, but it did not appear suspicious and apparently started in the rear of the home, Clay said. The house was destroyed.

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