An unoccupied, abandoned structure caught fire in Baiting Hollow early Thursday morning, according to Riverhead Town police.
Police said the structure was set back in a heavily wooded area near 1751 Sound Ave. The structure was fully engulfed when firefighters arrived.
Police said there were no people at the scene when they arrived. Police and the fire department were notified of the fire at about 1:44 a.m.
No injuries were reported as firefighters put out of the fire and an investigation is underway into the cause.
Police said Riverhead detectives, the town fire marshal office and Suffolk County Police Arson Squad all responded as part of the investigation.
No cause of the fire was identified yet. Anyone with information is asked to contact police at 631-727-4500.