Portland Fire & Rescue is trying to locate a person who was seen near the Elephant's Delicatessen early Tuesday morning before it was heavily damaged by fire.
Investigators say the fire was human caused. They have not said how the fire was started.
The flames went up the side of the building an into the attic. It was difficult for firefighters to access the fire, even from the roof.
They eventually had to pour large amounts of water from the roof to drown the fire.
No injuries were reported.