The cause of a fire Wednesday night in South Portland that destroyed a truck filled with produce owned by the Hannaford supermarket chain is not suspicious, according to the city’s fire department.

An investigator from the state Fire Marshal’s Office agreed with local firefighters that the fire started in a refrigerator pump that cooled produce in the truck, said Robb Couture, spokesman for the fire department.

The fire destroyed the truck, spread to a second truck parked at the Hannaford distribution center at 54 Hemco Road and damaged warehouse loading bays. About 80 employees who were working in the warehouse at the time were evacuated.

“Hannaford is evaluating what property and product damage occurred, and will be working with our other distribution centers as necessary to supply stores in conjunction with the South Portland Distribution Center,” Hannaford said in a statement issued Thursday.