Fire and Emergency New Zealand are responding to reports of an explosion in Tongariro.
A spokesperson said 10 appliances are on their way from Whanganui, Rotorua and Palmerston North.
The incident reportedly occurred at a water bottling plant.
Police said there were reports of an explosion at the water treatment plant, but there were no reports of injuries.
At 11pm, the police were still waiting for specialist vehicles to arrive at the scene from Whanganui.