A former military aircraft has crashed into waters off Melbourne's Mornington Peninsula after colliding with another plane mid-air.
Emergency services were called to the incident at Port Phillip Bay, about 12km west of Mount Martha, at 1.45pm on Sunday.
Two Viper S-211 Marchetti light aircraft had collided with one plane crashing into the water, the Australian Maritime Safety Authority confirmed.
Two people were onboard the aircraft at the time.
The second plane, with another pilot and passenger, landed safely at Essendon Airport.
Three rescue helicopters are scouring the scene, along with water police and volunteer marine rescue units.
Some of the wreckage has been located.
The Australian Maritime Safety Authority will continue the search for the two missing people until last light.
The Australian Transport Safety Bureau will also investigate the incident.
The Viper S-211 is an Italian-made fighter plane, primarily used for Air Force training.
Australian Associated Press
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