Authorities say a fire engulfed a camper and unattached shed Sunday morning in Prosser. Benton County sheriff's deputies and firefighters responded about 10:30 a.m. to reports of a structure fire in the 12500 block of North Missimer Road. Deputies say the two structures were totally engulfed within minutes, but left the main residence undamaged, No one was injured in the fire. The homeowner reportedly told authorities they suspect an unattended space heater caused the fire.