The fire broke out a short time ago at the Camping World on River Avenue.
Upon arrival, firefighters reported heavy black smoke coming from one the buildings and immediately requested mutual aid as they engaged in firefighting operations.
There are no reported injuries at this time.
Rt. 9 is being shut for the scene in both directions between Cross and Rt. 70.
UPDATE 6:38 AM: The fire has been mostly contained.
The cause of the fire is under investigation.