A reveller has been airlifted by helicopter to hospital after suffering a serious injury while trying to jump into an ocean pool at a packed Aussie beach on Christmas day.

Police were told the man, aged in his 20s, slipped while jumping from a cliff into Bronte Pool in Sydney's East and hit his head on concrete about 4.30pm on Wednesday.

Emergency services rushed to the scene and treated the man for head injuries before transporting him to St Vincent's Hospital in a helicopter. 

A NSW Police spokesperson told Daily Mail Australia that officers are 'speaking with a number of people at the scene'.

The cliff is a popular jumping spot for beachgoers despite council erecting barbed wire and spiked posts to try and hinder the dangerous act.

Footage from the scene revealed the pool and nearby sitting area had to be evacuated while the man was being treated.

Officers also attended a nearby bus stop at 4.35pm following reports that a man had been assaulted.

Paramedics treated a man, who was reportedly unconscious while police speak with people at the scene to determine the circumstances surrounding the incident.

A man aged in his 20s has been flown to hospital in a helicopter after hitting his head trying to jump into an ocean pool on Christmas Day (pictured, emergency services at the scene)

A man aged in his 20s has been flown to hospital in a helicopter after hitting his head trying to jump into an ocean pool on Christmas Day (pictured, emergency services at the scene)

Witnesses told police the man was jumping into Bronte Pool (pictured) from a cliff and popular diving spot that has been blocked off by the council with barbed wire and spiked posts

Witnesses told police the man was jumping into Bronte Pool (pictured) from a cliff and popular diving spot that has been blocked off by the council with barbed wire and spiked posts

Emergency services have remained near Bronte Beach at the request of City of Waverley Council in response to an annual 'orphan's Christmas'.

Thousands of people descended on Bronte Park on Christmas Day to celebrate the holiday despite the warnings of increased patrols by rangers and police.

Last year, locals were left furious after plastic bottles, broken glass, food scraps, clothes and human waste were left strewn across the park after up to 10,000 people attended.

One local told Daily Mail Australia that they 'know to stay away from Bronte on Christmas' so as to avoid the packed beach and surrounding parklands.

While the crowd was well behaved, concerns about the mess left behind sparked an earlier warning issued from the City of Waverley Council to people planning to spend the day at Bronte Park and beach that authorities would be in attendance.  

Their apprehension towards the party grew as people arrived early on Christmas Day on foot, by car and on buses to battle for limited space at the beach.

But Mr Spicer said he is confident the steps the council has taken 'will make a big difference this year'.

He added that Bronte Park will receive 'crowd control pathways and temporary toilets' under the council's Summer Safe program.

 

Thousands of revellers have descended onto Bronte Beach for an annual Christmas Day party (pictured) which locals fear will result in the area being trashed like previous years

Thousands of revellers have descended onto Bronte Beach for an annual Christmas Day party (pictured) which locals fear will result in the area being trashed like previous years

The event has become a mecca for tourists and backpackers celebrating the holiday away from home and is affectionately known as 'orphans Christmas' (pictured, revellers)

The event has become a mecca for tourists and backpackers celebrating the holiday away from home and is affectionately known as 'orphans Christmas' (pictured, revellers) 

It was a stark contrast at 8am on Christmas morning but some had already reserved huts and set up gazebos at Bronte Park to get in early on the long day ahead

It was a stark contrast at 8am on Christmas morning but some had already reserved huts and set up gazebos at Bronte Park to get in early on the long day ahead

Revellers still swamped to the beach despite the warning of more patrolling council rangers and police at the beach in an attempt to combat unruly attendees

Revellers still swamped to the beach despite the warning of more patrolling council rangers and police at the beach in an attempt to combat unruly attendees

Waverley Council said it would not tolerate any bad behaviour and had taken 'a number of significant proactive measures to ensure our community can relax and enjoy the summer'.

'The safe enjoyment of our public and recreational spaces is our number one priority,' a spokesperson said.

'We encourage everyone to enjoy our beaches responsibly and safely, ensuring they remain a welcoming space for all.'

NSW Police said officers are conducting patrols of Bronte, Bondi and Tamarama beaches 'due to significant crowd numbers expected over the holiday period'.

Partygoers at Bronte Beach enjoying the 'orphan's Christmas'

Partygoers at Bronte Beach enjoying the 'orphan's Christmas' 

Christmas Day revellers enjoying the water

Christmas Day revellers enjoying the water

The police said they were aware of a party planned at Bronte on Christmas Day and had been working with organisers.

'There will be officers from Eastern Suburbs Police Area Command, assisted by specialist police, tasked to patrol the area to ensure the safety of visitors and manage crowd numbers,' a spokesperson said.

'People are reminded to check and abide by designated alcohol-prohibited and/or alcohol-free zones in the area. Alcohol and water don't mix.'

Beachgoers were also warned not to swim or drive boats when intoxicated and said they would have a 'significant presence' on the roads and in the water over the coming day