The fire that destroyed a popular Gwinnett County restaurant was accidental in nature, sparked by a sign left in the attic from a previous business, firefighters said Thursday.

No one was injured when flames went through the roof of Dreamland Bar-B-Que on Peachtree Parkway in Peachtree Corners on Jan. 16.

Firefighters credited the restaurant manager with clearing the restaurant of patrons after calling 911.

“Due in part to the quick thinking and actions of the manager, many lives were spared,” Colin Rhoden, spokesman for Gwinnett County fire, said in an emailed statement. “His actions not only ensured the safety of those at the restaurant, but also assisted the responders to the fire incident.”

Investigators determined a neon sign transformer located in the attic space, left from a previous restaurant, sparked the fire, Rhoden said.