Australia day plane crash: Two people killed as twin-prop aircraft plummets into Perth river

'He flipped straight down hard in the water. It looked like he just broke in half as he hit it'

Two people have died after a twin-prop aircraft plummeted into Perth’s Swan River.

Numerous bystanders, who had gathered to celebrate Australia Day, looked on in horror.

Video footage showed the plane flying low over the water, before swerving downwards and crashing into the river.

"As he banked left he seemed to go further to the left ... and lose forward momentum and lost altitude fairly quickly," eyewitness Lloyd Douglas told ABC.

He added: "My concern was that he'd landed in amongst all the small boats up at the east end of the Perth water.

"It did hit the water with a fairly decent force, and goodness if it had another boat in the water or something it would be a tragedy."

Another bystander told the broadcaster: "He flipped straight down hard in the water. It looked like he just broke in half as he hit the water."

The city's planned Skyworks show, a popular annual event which includes stunt planes and fireworks, has been cancelled.

Perth's Mayor, Lisa Scaffidi, announced the changes on Twitter.

Locals on boats, assembled for Australia Day celebrations, attempted to help save the pilot and passenger, 7 News reported, but were unable to help them.