Eastside Fire and Rescue personnel put out a residential fire at an unoccupied home on the 3100 block of 213th Place Southeast in Sammamish Friday morning.

King County’s Fire Investigation Unit determined soaked rags left out on the front porch spontaneously combusted causing the fire.

Firefighters responded to the blaze before 3:30 a.m. and quickly began an offensive attack and search for occupants. No one was found inside the home and the fire was out by 4:20 a.m.

Fire investigators began looking into the cause of the fire shortly after it was put out.

The house is valued at $650,000, according to county’s records.

Additional reporting by Megan Campbell.