Crews respond to the boy critically injured in the shark attack.

In short:

Police have praised the friends of a 12-year-old boy who was bitten by a shark in Sydney’s east on Sunday.

The group were jumping off a 6-metre rock ledge in the Vaucluse area when the attack happened.

Police said his friends jumped into the surf before water police arrived with medical tourniquets to apply to his legs.

The quick response from the friends of a 12-year-old boy critically injured in a shark attack at a Sydney beach saved the boy’s life, police say.

Emergency services were called to Hermitage Foreshore Walk near Shark Beach at Vaucluse about 4:20pm on Sunday.

The boy sustained critical injuries to both legs and was taken to the Sydney Children’s Hospital at Randwick, where he was placed in intensive care.

The boy was pulled aboard a vessel by water police officers, who attached two medical tourniquets. (ABC News: Nick Dole)

Marine Area Command commander Superintendent Joseph McNulty said today “every second counted” and the quick response by the boy’s friends helped the boy survive the attack.

“The actions of his mates who have gone into the water to pull him out have been nothing but brave, a gallant recovery from his mates, there,”

he said.

Superintendent McNulty said after being initially helped by those around him, the boy was pulled aboard a vessel by water police officers, who attached two medical tourniquets and administered first aid.

He said it was a “textbook recovery”.

“He’s in for the fight of his life now and the actions of emergency services yesterday gave him that chance,” Superintendent McNulty said.

“It was a horrendous scene at the time when police attended. We believe it was something like a bull shark that attacked the lower limbs of that boy yesterday.”

Emergency crews were called to a beach at Vaucluse after a 12-year-old was bitten by a shark. (ABC News: Nick Dole)

Bad weather may have led to shark activity

He said heavy rainfall over the weekend may have contributed to the attack.

“At the time yesterday, the boys were jumping off a 6-metre rock that’s popular in the Vaucluse area into that brackish water,” he said.

“We believe the combination of the brackish water, the fresh water, the actions of the splashing, may have made that perfect storm environment for that shark attack yesterday.

“But thankfully, what I can say — that boy is fighting for his life now.”

He also said that the boy was rescued from the water by police officers “within minutes” of the Triple Zero (000) call being made.

Footage from the scene showed him being treated by paramedics in a blue police rescue tent.

Police praised the efforts of his friends who jumped into the water to help rescue him. (ABC News: Nick Dole)

In a statement, the Department of Primary Industries and Regional Development (DPIRD) said it had assisted in the rescue, and believe a bull shark had been involved.

“DPIRD shark scientists are unable to definitively confirm the species based on photos of the injury,” it said.

“However they believe a Bull shark was likely responsible based on the nature of the injuries and the environmental conditions at the site.

“Our thoughts are with the boy, his family and the other young people who witnessed the incident.”

Premier praises bravery

Premier Chris Minns has praised the efforts of those who worked to save the boy’s life.

“I just want to give a shout out to the young people who were in the water that got the young man … and did everything possible to save his life,” he said.

“I think that was a brave thing to do.”

Mr Minns said he felt for the victim and his family.

“We’re all thinking about him and his family in [what was] a tragic, tragic day in Sydney,” he said.

Agriculture Minister Tara Moriarty said there were a significant amount of bull sharks in Sydney Harbour.

“The Department of Primary Industries and Regional Development is working with other authorities to identify the shark involved in this really terrible attack,” she said.