Investigators are at the scene of a house fire that broke out near Alliston on Sunday.

The fire which broke out on Atkinson Crescent is considered suspicious.

Today the Office of the Fire Marshal combed the scene, trying to figure out what happened.

On Sunday firefighters were called to a house in a new subdivision just east of Alliston. No one was home when the fire broke out.

While the damage wasn’t visible from the outside New Tecumseth Fire Chief Dan Heydon says it was extensive.

“Heavy smoke damage,” he said at the scene on Sunday. “Subsequent to the investigation and putting out the fire we’ve notified the Office of the Fire Marshal. We’re kindof concerned about where the fire started, and there is large dollar loss. We’ve actually had fire damage on all three levels.”

OPP officers were called to the scene on Sunday, and returned to investigate today.