A fire was started deliberately in the cellar of a disused restaurant yesterday.
The blaze spread to the ground floor of the Rialto Restaurant on Hermitage Street in Rishton.
Firefighters said no one was evacuated from the building but are treating it as suspicious.
John Taylor, of Lancashire Fire and Rescue Service, said: "Crews from Hyndburn were called to a rubbish fire suspected to have been started deliberately in the cellar. They put it out before it could spread to the ceiling above and damage the ground floor more. No rescues were made.
"Four square metres of timber were destroyed by fire and there was light smoke damage to the kitchen of the property."
Four breathing apparatus, two hose reels and a triple extension ladder were used by firefighters who tackled the fire at around 10.30am on Sunday, May 22.