BREWER, Maine -- Nov. 8, 2019 -- A fire broke out at the site of a new restaurant in Brewer on Friday evening.

A large Friday evening fire destroyed a Brewer restaurant that was supposed to open this winter.

The fire started just after 5 p.m., and almost an hour after the fire started, the roof of the restaurant had completely burned down and the inside was ablaze. Just before 6:30 p.m., Bangor fire department reported that from the Bangor waterfront, they could not see any more flames.

The structure fire broke out at the site of Whiskey River Smokehouse, a restaurant that was set to open and has been under construction on South Main Street. The Save-a-Lot parking lot in Brewer was swarming with firefighters from Brewer, Bangor, Holden, Orrington and Eddington as the building burned.

A Bangor Fire Department crane sprayed water from one side of the building as a group of firefighters hosed down the other. Firefighters broke windows and were spraying water from outside. The inside was completely ablaze.

No one was inside the building when the fire started, and the roof is completely gone. The cause of the fire is unknown, according to Jason Moffitt, Brewer chief of police. The police department will conduct an investigation along with the Maine fire marshal’s office.

Approximately 20 firefighters from multiple departments are on the scene. South Main Street near the intersection of Wilson Street in Brewer is closed, and motorists are advised to use alternative routes.

Watch: Crews are on the scene of a large structure fire in Brewer