Ohio State Fire Marshal investigators have returned to the scene of a fire that claimed the lives of three young children in Bridgeport.

Family members said the three children who lost their lives were ages 2, 4 and 5.

The parents remained in a Pittsburgh hospital fighting for their lives as of Monday morning. Both parents suffered burns and are relying on ventilators, family members said.

The fire ripped through four apartments as well as the B & D appliance store along Main Street in Bridgeport on Sunday around 11 a.m.

The Bridgeport assistant fire chief said firefighters had challenges putting out the blaze because of the building's layout. Crews were at the scene for hours battling the blaze, and smoke and flames were visible well into the afternoon.

There are many questions left to be answered as investigators work to find out what caused the building to catch fire.

"The building was smoking really bad," said Crystal Whitacre, a witness. "They started to go on the roof and they punched a hole down into the roof and that's when all the smoke and the flames came out through there."

Police were forced to close Main Street while fire crews from several departments tried to douse the flames. The road was closed until after 5 p.m.

The family is asking for donations of any kind since it had no insurance. Those donations can be made to Wilson Funeral Home on National Road in Bridgeport.

A water line break in the same area as the fire led to issues for crews trying to fix the break. Water could not be shut off until the blaze had been taken care of, but once it was, crews were able to start making repairs.

Once water service is restored, a 48-hour boil order will be issued for customers who were affected.

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-March 17, 2013: Family: Fire kills 3 children; Parents hospitalized