A mobile home burned Monday night in Petaluma on the Sampson compound, a group of several family-owned parcels on Liberty Road.
Officials called the fire suspicious.
Firefighters were dispatched to reports of a blaze there at 7:43 p.m., emergency dispatchers said.
Neighbors reported large plumes of smoke in the neighborhood near Skillman Lane on Petaluma's west side.
The first engine from the Rancho Adobe Fire Protection District arrived on the scene at 7:50 p.m. and firefighters found the mobile home fully engulfed in flames, dispatchers said.