Passengers in the plane were confirmed dead at the scene and had yet to be identified.
Two small planes collided Wednesday, killing four people and scattering debris across grassland in southeastern Australia.
Police and other emergency services were at the two separate crash scenes in Mangalore, north of the Victoria state capital, Melbourne.
Victoria police said in a statement two occupants in each plane were confirmed dead at the scene and had yet to be identified.
Aerial images taken from local media showed debris from two small planes in grassy areas.
The Civil Aviation Safety Authority and the Australian Transport Safety Bureau have been notified.
