THIS is the chilling moment a seaplane is filmed moments before it crashed into a Sydney river killing six people.
The seaplane was returning from a New Year's Eve lunch at a picturesque restaurant on the NSW Hawkesbury river when something caused it to plunge into the water and rapidly sink, killing all six aboard.
The Sydney Seaplanes aircraft was carrying a pilot and five passengers when it crashed at Cowan Creek, Jerusalem Bay east of Cowan about 3pm on Sunday. Police divers recovered six bodies soon after.
Dramatic footage has emerged appearing to show the plane, which is currently sitting in 13m of water, flying through the sky just seconds before it came down at around 3.15pm local time.
Those on board were enjoying a "wine and dine" sightseeing flight ahead of the New Year's Eve celebrations in Sydney.
The operator, Sydney Seaplanes, said it was "deeply shocked" by the tragic accident and had suspended all operations until further notice.
"We wish to pass on our heartfelt condolences to the family and friends of the passengers and pilot who were tragically killed," managing director Aaron Shaw said in a statement.
"We do not yet know the cause of the accident.
"We are dedicating our full resources in assisting the NSW Police, the Australian Transport Safety Board, Civil Aviation Safety Authority and other relevant authorities to understand the cause of the accident."
The British Foreign office was in touch with Australian officials amid reports that UK nationals died in the crash.
"Officials from the British consulate are in contact with local authorities in relation to a sea plane accident near Sydney," a spokeswoman said. "We stand ready to provide consular assistance."
Superintendent Michael Gorman told reporters on the scene on Sunday the passengers had been returning to Sydney after dining at a restaurant on the Hawkesbury.
The plane was believed to have been travelling from the Cottage Point Inn to Rose Bay, Supt Gorman said.
Myles Baptiste told the Nine Network he saw the plane flying towards him about 500 metres away when it hit the water.
"It made a tight right-hand turn and as it actually turned around, the wings dipped and it nosedived straight into the water," he said.
Supt Gorman said police air crash investigators would on Monday comb over the plane for clues about what caused the crash.
The ages and identities of those aboard the plane are unknown, but an 11-year-old British boy is believed to be one of the victims.
A UK Foreign and Commonwealth Office spokeswoman said: "Officials from the British Consulate are in contact with local authorities in relation to a sea plane accident near Sydney. We stand ready to provide consular assistance."
The Westpac Life Saver Rescue Helicopter found an oil slick and several items of debris on the surface of Cowan Creek, spokesman Stephen Leahy told AAP.
"There appeared to be a silhouette or outline of a small aircraft but it appeared to be submerged in deep water," he said.
The ATSB said the single-engine DHC-2 Beaver Seaplane "sunk rapidly" after hitting the water.
"The sequence of events leading up to the accident are not yet understood, however following the impact with the water, the aircraft is reported to have sunk rapidly."
The company, which has been operating since 2005, provides flights above and around some of Sydney's most popular tourist sites including the Opera House, the Harbour Bridge, Pittwater and the Hawkesbury River region.
Today, police dive crews are preparing to refloat the wreckage of a seaplane.