‘Worst possible outcome’: Grave fears for boy mauled by shark

There are fears for the life of a young boy mauled by a shark in Sydney after a family friend said "the worst outcome possible" loomed.

Nico Antic, 12, was attacked by a suspected bull shark as he was jumping off a rock face at Neilson Park, near Shark Beach in Vaucluse, on Sunday.

The boy's friends jumped into the water to pull him to safety, but Nico suffered serious leg wounds and has been in a critical condition in hospital ever since.

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The organiser of an online fundraiser, who claims to be a close friend of the Antic family, said the worst was now feared after the boy's "devastating" injuries.

"Despite all efforts, this heartbreaking event has led to the worst possible outcome," Victor Piñeiro wrote in an update.

"We are raising funds to help the Antic family cover upcoming expenses and related arrangements during this incredibly difficult time.

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"Any contribution, no matter the size, would be deeply appreciated and will help ease the financial burden as they grieve. All funds will be donated to the Antic family."

The fundraiser has brought in more than $77,000.

Nico, a junior lifesaver, was the first of four shark attack victims in 48 hours on NSW beaches this week.

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An 11-year-old boy had a lucky escape on Monday after a shark bit his board but otherwise left him unscathed.

Later that same day, a surfer, since identified as 27-year-old musician Andre De Ruyter, was attacked in the water at a Manly beach.

He was pulled to shore by bystanders and remains in a critical condition, with part of his lower right leg amputated.

And yesterday, a man was attacked at Point Plomer, north of Port Macquarie.

The man sustained minor injuries and has since been discharged from hospital.

The weekend's heavy rain has stirred up beachside waters and made them murky and opaque, providing an ideal environment for shark attacks.

People have been advised to steer clear of murky water, and multiple beaches remain closed.

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