Police have confirmed that three men and a woman were on a light plane that crashed off the coast near Point Lonsdale on Friday afternoon.
A 68-year-old Noble Park man, a 63-year-old Black Rock woman, a 65-year-old Black Rock man and a 55-year-old Mordialloc man were on board the aircraft that took off from Moorabbin airport in the morning.
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Plane crashes at Barwon Heads
Three people are confirmed dead after a plane crash at Barwon Heads, near Geelong. Vision courtesy Nine Network.
Three bodies have been recovered from the water. It is believed the fourth person was also killed, but their body is yet to be located.
Late on Friday night a Victoria Police spokeswoman said the families of the deceased people had been notified, but the bodies were yet to be formally identified.
The search of the area was called off for the night just before 8pm. It will resume again early on Saturday morning.
Inspector Graham Banks, of Geelong police, said a fisherman had seen the plane come down at 12.30pm on Friday about two kilometres off Collendina Beach, which runs between Point Lonsdale and Barwon Heads.
"He called police shortly thereafter. He was in a boat and he went out and observed that clearly a plane had impacted the water and dispersed over a wide area and there were three persons that were clearly deceased at that time," Inspector Banks said.
The witness, who was within a kilometre of the crash, heard the roar of the plane's engine before seeing it plunge on its side into the water.
Another fisherman described following an oil slick in the ocean before locating the wreckage, which had sunk to the water's bottom. He, and others, volunteered to help with grid searches to locate parts of the wreckage.
The plane flew from Moorabbin Airport, but police would not reveal where the plane was headed to. There was no distress call made by the aircraft - a six seater Piper PA-28 Cherokee.
The crash site appears to be near the wreck of the HMAS Canberra, a former navy vessel that was sunk to create a dive site in 2009. The main part of the plane has sunk about 30 metres into the ocean.
It is not yet known what caused the plane to go into the water. Two Australian Transport Safety Bureau Investigators with expertise in engineering and "human factors" will head to the scene tomorrow.
They are expected to remain there for two or three days and will examine recovered wreckage and interview witnesses.
As debris began washing ashore near Point Lonsdale on Friday afternoon, disaster victim identification police arrived along with the coroner to begin the grim forensic examination.
Boats from several organisations, including Parks Victoria, are assisting in an expanding square search from the initial site in a bid to find debris. Two air ambulance helicopters were sent in response to the crash.
Fishermen Peter Lewry and Graeme McLean said they saw a light plane flying low in the sky off the Queenscliff bay.
"We both commented to each other how low it was coming out of the rain," Mr Lewry said.
"The engine was fine; there was no coughing or spluttering."
He said the conditions for flying were bad. "It was very wet, extremely overcast," he said.
There were no requests for emergency landing at two of the airports closest to the crash, at Torquay and Barwon Heads.
A spokesman for Barwon Heads Airport said conditions had been "marginal", and that helicopter flights from the aerodrome had been cancelled on Friday because of the weather.
Members of the Ocean Grove Surf Lifesaving Club are assisting at the scene of the crash.
The Queenscliff boat ramp will be closed on Saturday while police search the area and assess any wreckage from the crash.
We can confirm 3 people have been located deceased in the Barwon Heads plane crash. We will provide further details as they come to hand.— Victoria Police (@VictoriaPolice) January 29, 2016
Air ambulance over scene of reported plane crash near Barwon Heads, Victoria. Several passengers feared dead. pic.twitter.com/ZT3lSSZg48— Samuel Clark (@sclark_melbs) January 29, 2016
I'm very sorry to hear of the plane crash in Barwon Heads today. @DarrynLyons— Geelong Mayor (@Geelong_Mayor) January 29, 2016
With Chloe Booker and Aisha Dow