MONTGOMERY — Authorities are investigating a fire that destroyed the former County Line Inn restaurant early Sunday morning.

   Township fire companies were called to the Route 206 building at 2:50 a.m. Sunday, according to the Somerset County prosecutor’s office. On arrival, they found large amounts of heavy smoke coming from the building, which was under renovation.

   Flames spread from the lower level of the structure upward through a stairwell and an elevator shaft. The first floor became completely engulfed, and the intensity of the fire caused the roof and floor to collapse. Firefighters brought in an excavator to remove the remaining walls so that the fire could be extinguished.

   County Prosecutor Wayne Forrest said that due to extensive damage to the structure and the large amount of water that accumulated in the first-floor area, the Arson Task Force could not yet conduct an origin and cause examination.

   The building, which has housed a string of different restaurants over the years, was owned and being renovated by Tusk, LLC, owned by Christopher Chang.

   Anyone that has any information concerning the fire is asked to contact either the Montgomery Township Police Department at 908-359 -3222, the Somerset County prosecutor’s office Arson Task Force at 908-231-7100, or the Somerset County Crime Stoppers TIPS Line at 1-888-577-TIPS (8477) or online at www. 888577tips.org. All calls are confidential.