Police have confirmed three people are dead after a plane crashed into the ocean in Barwon Heads, as the search continues for a fourth person.
The plane crashed into the water just before 12:30pm at Collendina Beach, which lies between Barwon Heads and Point Lonsdale.
A fisherman witnessed the crash and called authorities immediately.
"That witness is extremely distressed. That person was reasonably close, within a kilometre," Inspector Graham Banks told media at a press conference held on Friday afternoon.
Police have confirmed the plane -- which is possibly a four seater aircraft -- left Moorabbin Airport this morning and there was no record of a distress call from the plane before it crashed.
EARLIER: It is not known at this stage how many people were on board, what sort of plane was involved or the cause of the crash -- but a Victoria Police spokeswoman told The Huffington Post Australia that "it was not a large plane... not like a QANTAS plane."
The incident was said to have occurred near Bridge Road, running right near the ocean
"At this stage we believe a number of people are deceased. The cause of the incident is not yet known and we will provide further details once they come to hand," a police statement said.
Some media reports claim up to five people may have died in the crash.
The police spokeswoman said police and emergency services were on the scene but little other information was available at the time.
The ABC reports two air ambulance helicopters and two boats have been dispatched to the area. Aircraft tracker websites show a search helicopter appearing to circle above the area where the plane was said to have gone down.
9 News Melbourne tweeted pictures from a helicopter, allegedly showing a search boat finding pieces of wreckage.