Fire devastated the Jenny Lee Bakery and its main production facility in McKees Rocks yesterday afternoon.

Fire Chief Nick Radoycis said the 1:40 p.m. blaze started in the second floor of one of three adjoining buildings that make up the landmark facility in the 600 block of Island Avenue. It's called the "Candy Room," where employees make peanut brittle, chocolates and other treats.

He said about 10 people were working on Thanksgiving Day. All escaped unharmed.

The cause of the fire has not been determined. The Allegheny County fire marshal was called to the scene to investigate.

The fire quickly escalated to five alarms. Eight fire companies reponded and remained at the scene for about three hours.

"It seems most of the fire damage was in two (second-story) rooms in the front of the building, and there doesn't seem to be much structural damage," said Bernard Baker, company president. "But there was a lot of water damage on the first floor and in the basements. I hope we can get it cleaned up soon because December is our busiest month of the year."

Mr. Baker said he'll meet with insurance company representatives today to assess damage and see what will be necessary to resume business.

"If I know them, they'll be back in business soon," Chief Radoycis said. "Christmas is a big season for the company. They had a similar situation a while back."

He was referring to a four-alarm fire at the same place in March 1994, one week before Easter. Dozens of employees and volunteers pitched in and two days later, Jenny Lee Bakery products were being shipped to supermarkets and company-operated outlets in time for holiday sales.

Damage was more extensive to the three-building complex this time, the chief said.

"We had to open the roof of the three-story building," he said, where the fire had spread and rolled up the walls from the second and third floors. "There's smoke and water throughout the place."

Jenny Lee Bakery in the heart of town has been a fixture in McKees Rocks since Mr. Baker's father, Paul Baker, opened the first store in 1938. Two other retail outlets are located in Market Square in Downtown Pittsburgh and in the Crafton-Ingram Shopping Center.

The McKees Rocks facility has about 45 full- and part-time employees.