A fire at Heinz Wattie's is being treated as suspicious by fire investigation services.
Hawke's Bay senior station officer Collin Littlewood said the fire service was called out just after 2am yesterday morning to a "sprinkler alarm operation" at the King St North production facility.
"When we got there, there was lots of smoke - the sprinkler had held the fire in the area so it did not spread."
Five fire trucks from Napier and Hastings were sent, and crews with specialist equipment removed and extinguished plastic bottles and pallets that were burning in the covered area, only half of which had walls.
"Most of it was smoke - there was a lot of paper and cardboard, but plenty of ventilation."