A spark-spewing electrical fire erupted on the roof of a social service organization before dawn Monday in Golden Valley and left the nonprofit in tough shape heading into a crucial time.

The flames struck PRISM (People Responding In Social Ministry), located in the 700 block of Florida Avenue S. No one was in the building at the time, and no firefighters were hurt while knocking down the blaze in windy and icy conditions, said Fire Chief John Crelly.

PRISM provides people in need with many services, including food, clothing and household items, car loans, financial assistance, school supplies, items for holidays and birthdays, home maintenance and budget counseling.

The fire came just as PRISM was gearing up to distribute hams and turkeys to families in its foodshelf through the holiday season.

"We serve 550 families in a typical month, and needs are especially high for Thanksgiving," said Michelle Ness, PRISM's executive director. "We are left without power, suffering smoke damage, and will assess our short- and longer-term recovery needs."

Fortunately, Ness continued, "the outpouring of support from the community is wonderful. Families in need are able to access other social service organizations such as ICA [Foodshelf] or Jewish Family and Children's Services for help."

Authorities were alerted to the fire about 5:50 a.m. as workers in an adjoining packaging materials business arrived for their shift and noted that "it looked like the Fourth of July with all the sparks being thrown in the air" from the roof, Crelly said.

Firefighters traced the source of the fire to an electrical distribution system on the roof, the chief said. Once the power was turned off, fire crews went to work and had the scene cleared by 8 a.m., he said.