A young boy is in critical condition after being attacked by a shark. Picture: Sky News

Cops have praised a group of friends for saving a young boy, who is fighting for life after being attacked by a bull shark at a popular rock jumping Sydney Harbour beach.

The 12-year-old was with friends at the rock jumping point at Hermitage Foreshore Walk near Shark Beach in Vaucluse about 4.20pm Sunday when he was bitten by a shark.

His friends bravely worked together to pull him from the water, police said, exposing themselves to his “confronting” injuries in the process.

A young boy is in critical condition after being attacked by a shark. Picture: Sky News

The boy was attacked while jumping from rocks at the popular beach. Photo: Gaye Gerard /NewsWire

Multiple crews, including intensive care paramedics and aeromedical teams, rushed to rescue the boy who sustained critical injuries to his legs.

He was transported by boat to Rose Bay, where he was taken to the Children’s Hospital in Randwick.

Senior Constable John Morris told Sunrisethe boy had “double tourniquets” applied to his legs by paramedics and police on the rock shelf.

“The double tourniquet system, we think stemmed the loss of blood at that scene,” he said.

He has since undergone surgery and remains in a critical condition with his parents by his side.

Speaking to reporters on Monday, he said the boy lost a significant amount of blood and was unconscious when paramedics arrived.

“The boy had lost his pulse, there was a large blood loss and the double tourniquet stemmed that flow of blood loss yesterday, and has contributed to saving his life,” he said.

The boy sustained injuries to his legs. Picture: NewsWire / Justin Lloyd

Friends praised for ‘brave’ act

Constable Morris told reportersthe boy was jumping off a six-metre rockwith a group of teenage friends when the attack happened.

“We believe the combination of the brackish water, the freshwater, and the actions of the splashing may have made that perfect storm environment for that shark attack yesterday,” he said.

He told Sunrise the water had become “muddy” after the bouts of rain over the weekend.

“(The boys) werejumping into muddy water and what we believe is a shark was in the

vicinity has bitten that boy’s legs,” he said.

“One of his mates did jump in to pull him from the water’s edge to that rock platform as well, so he contributed to saving his life as well yesterday.”

The boy sustained injuries to his legs. Photo: Gaye Gerard /NewsWire

The boy remains in a critical condition. Photo: Gaye Gerard /NewsWire

He told reportersthe group of friends who pulled the boy from the water were “brave”.

“We can confirm … one boy definitely entered the water to pull his mate out and the other boys assisted them up from the water onto the rock platform, and that was just before the police (arrived),” he said.

“So those actions of those young men are brave, under those circumstances, and very confronting injuries for those boys to see.

“But I suppose that’s mateship.”

Cafe manager Gene Arkoudis said the attack happened at a popular jumping spot. Photo: Gaye Gerard /NewsWire

‘Very strange’: Shark attack at popular jumping spot

The Nielson general manager Gene Arkoudis said the area was “very quiet” at the time of the incident due to the weather, prompting staff to close the beachside cafe early.

That was when he got a call from a staff member about the shark attack.

“We did have certain staff on site for events and they contacted me straight away saying there’s been a shark attack here … like right in front of the main kiosk,” he told NewsWire.

Mr Arkoudis has been working as the cafe’s general manager for six months, and said he had never heard reports of sharks in the area.

In front of the cafe is a “huge” shark net that extends to the ocean floor, but he had only ever seen dolphins and the odd stingray in the waters.

“It was very strange to hear it happened right here,” he told NewsWire.

He said the group of boys were jumping from a popular spot that other locals often enjoyed.

“That was a particularly common jump spot – I’m a local, I’ve been doing that for years,” he said.

“We’ve all jumped off there into the water, and it’s risky – it’s an open ocean. You’re not in a net, you’re in open ocean.

“Unfortunately, the poor kid has jumped right into it.”

Mr Arkoudis said the friends who jumped in to save the 12-year-old were heroic.

“If you think about it, his mates are heroes,” he said.

“They pulled him out … and waited for police and ambulance. They did very well for 12-year-old boys.”

Police have praised the group of friends for pulling the boy to the rocks. Picture: Sky News

Boy likely attacked by bull shark in ‘muddy’ waters

He said the attack is believed to be from a bull shark.

“We believe it has the characteristics of a bull shark, but we’re working with our (Department of Primary Industries and Regional Development) fisheries today to do further identification and our safety message for swimmers across NSW,” he said.

Agriculture Minister Tara Moriarty said the Department of Primary Industries and Regional Development (DPII) were working to identify the shark.

“This is a tragic shark attack on a young boy having a swim on a Sunday afternoon in a harbour beach in Sydney’s east,” she said on Sunday.

“Our thoughts are with the young boy and his family. I understand there were also a lot of young people on the beach at the time of the attack, our thoughts are also with them.”

Police and the DPII believe a bull shark attacked the young boy.

Warning to swimmers after ‘brackish’ water

Constable Morris urged visitors to avoid swimming in the mouth of river and the Sydney Harbour Cove River where the water is “brackish”, a mixture of fresh and saltwater usually found where a river meets the sea.

“Yesterday’s water was extremely brackish because the large amount of rain Sydney has experienced over the over the weekend,” he said.