(La Porte, IN) - The cause of a fire that heavily damaged a house last week in La Porte remains under investigation.

The single-story home caught fire Thursday at about 6 p.m. at 1325 Federal Avenue.

Though heavy smoke was coming from the structure when firefighters arrived, Assistant Fire Chief Kelly Burke said nobody was home at the time of the blaze, and there were no pets inside.

"The homeowners were both at work. They had been gone for several hours," Burke said.

Burke says it appears the fire began in the living room, but the damage was extensive enough to make it more challenging to uncover the source of the fire.

Burke said it's possible the house could be ruled a total loss because of the damage.