GROVE CITY — A woman died this morning when fire destroyed a duplex.

The office of Mercer County Coroner Bradley McGonigle III confirmed the death this morning and said it was under investigation by state police in Mercer.

Neighbors of the duplex at 132 Garden Ave. said a woman ran back into the building while it was ablaze and never came back out.

Bonnie Schaefer, who lives at the corner of Garden Avenue and Craig Street, said a woman went back to look for her dog.

"She went back in and couldn't get out," Schaefer said.

She said a firefighter tried to save the woman, but couldn't make it past the flames and smoke.

Schaefer and other witnesses think the firefighter was taken to a hospital for treatment of unspecified injuries.

Along with an investigation of the fire by the state police fire marshal from New Castle, Dominion-Peoples Gas Co. also sent an investigator to the scene to check whether the natural gas service to the house had anything to do with the fire.

"His investigation will determine if there was a leak as well as if the cause was natural gas," said Elmore Lockley, gas company spokesman.

Schaefer said firefighters had a difficult time fighting the blaze because of the frigid conditions. She cited frozen hydrants among the problems.

Erma Reagle, who lives at the end of the street, saw the building was on fire about 6 a.m.