Bonduelle Canada says it has not confirmed the cause of the fire at its Tecumseh plant but suspects an electrical problem, adding damage is extensive and it will likely be difficult to continue normal production.
It says the plant, which caught fire overnight, produces nearly 30,000 tonnes of frozen goods and 20,000 tonnes of canned goods, mostly for Green Giant for whom Bonduelle is the exclusive Canadian supplier.
Town officials urged residents to leave the area Friday morning, fearing that smoke irritants and hazardous materials could cause health risks.
Residents, who were offered shelter at the town's arena and a nearby school, were later told they could return to their homes.
The state of emergency was lifted in the afternoon and the public was asked to steer clear of the area. Residents were encouraged to keep their doors and windows closed due to drifting smoke.
Tecumseh fire Chief Doug Pitre says that two holding tanks have been filled with ammonia from the plant, which might have become a hazard if the fire had not been contained.
Pitre said firefighters determined there was no risk to human life inside the building, and no injuries have been reported.
But he says the extensive damage could injure the company's bottom line.
"It's possible they could still continue the freezing operation, it depends on the electrical," Pitre said.
"Without their freezing operation nothing can be shipped, and they are in their busiest season now," he added.
Windsor fire Chief Bruce Montone said several units from his team along with firefighters and officers from neighbouring communities were dispatched to assist Tecumseh's efforts.
Montreal-based Bonduelle Canada says its executives are headed to the site and will meet with employees and local authorities once there.
The company said more information about delays in production will be released once a detailed examination of the damage is completed.
"Bonduelle will take all necessary measures to minimize the impact of this tragedy on its employees and customers," it said in a release.
The company says the plant has 200 employees on permanent contracts and 450 seasonal employees. It says 110 farmers provide their goods to the plant, farming 7,000 hectares of farmland.
— By Anne-Marie Vettorel in Toronto