Crews on the ground and in the air are fighting to put out a vegetation fire in rural Whanganui

Fire and Emergency says the blaze near Parikino, which broke out before 5:15pm, has grown up to three kilometres in width.

Nine fire trucks, four helicopters, and multiple support vehicles are in attendance.

It says the fire is burning a mixture of pine trees and other vegetation across several gullies.

There is no indication the blaze is a threat to any structures or will affect State Highway 4.

Some nearby residents tell our newsroom they are prepared for evacuation if necessary.