Vigilance Hose firefighters responded to the scene behind the department where they found Chief Jerry Johnson using a fire extinguisher around 1 p.m., the fire department said.
Engine 5012 responded with a crew of 5 firefighters who used a hand line, cooled down the vehicle and protected exposures.
Station 50 crews were assisted by Upper Nazareth Station 54 (5412) and Nazareth Ambulance, fire crews said.
No injuries were reported and the cause was under investigation.
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