At 0504 hrs, the Bergenfield Fire Department responded to 507 South Washington Avenue for a reported fire at the Thrift Shop. 740 was first due and called a working fire on the roof. On arrival, Engine 744 stretched a line to the roof along with the ladder crew. A fire was found on the roof area with no major fire extension into the building, but there was a decent smoke condition in the structure. Bergenfield crews worked inside the structure opening ceiling tiles and using tarps to cover merchandise while the truck opened the roof and searched for any extension. Units operated on scene for 90 minutes. New Milford FD responded to the scene as our FAST team. There were no injuries to any civilians or firefighters and the cause of the fire is under investigation.