It was first reported just after 11 pm Thursday in a strip mall on the northwest corner of Cedar and Shields.
Firefighters responded for smoke coming from the building.
They were told people were inside, but after a search, no one was found.
Firefighters say debris was burning inside the vacant store.
It's believed unhoused people may have been inside the building before the fire.
The flames did not spread to the building itself.
No one was hurt.