The Sparta Township Fire Department responded to the Sparta Classic Diner just after 11:55 p.m. on Thursday, July 21, the squad said.
Upon arrival, crews confirmed heavy flames coming from the kitchen and billowing through the roof.
Firefighters worked diligently, stretching multiple hose lines through the building to get the blaze under control just before 1 a.m., the department said.
Meanwhile, one firefighter suffered from heat exhaustion and was treated at the scene as crews were packing up, authorities said.
No other injuries were reported, and the scene was cleared just before 2:25 a.m.
The cause of the fire remains under investigation.
Assisting agencies include fire departments in Andover, Ogdensburg, Hardyston, and Jefferson, as well as Sparta EMS and the Sparta Township Police Department.
Scroll down to view additional photos from the scene of the blaze.
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