An Indigenous teen was kicked and pinned to the ground by police on Monday. His family want justice.

NSW Police were patrolling Eddie Ward Park in the inner-Sydney suburb of Surry Hills on Monday when they came across a group of teenagers.

What happened between then and the moment a teen switched on his phone camera is unclear, but what went down next was captured on film.

The group and the three officers argue, before a 16-year-old boy can be heard saying “I’ll crack ya across the jaw, bro”.

The male police officer then walks towards the boy and orders him to turn around, holding his hands behind his back.

The officer then kicks the legs out from under the boy causing him to fall to the ground face first. Two female officers help to hold him down as he is handcuffed.

The teen, who cannot be named under NSW law, was treated for minor injuries at St Vincent's Hospital before being released without charge.

A family member said in a post on social media that the teenager had sustained a bruised shoulder, cuts and grazing to his knee, face and elbow and chipped teeth, and they were awaiting the results of x-rays, NITV reported.

"That's just appalling".

The constable involved, who has been in the police force for three years, has been placed on restricted duties while a review is carried out.

"An investigation into the circumstances surrounding the arrest is now underway by officers attached to the Professional Standards Command," a police statement said.

Nathan Moran from the Metropolitan Local Aboriginal Land Council told ABC the arrest was an example of heavy-handed policing.

"Flicking the kid face-first onto a hard ground ... that's never warranted," he said.

"Yes, I acknowledge he made some inappropriate verbal threats but you could see that nowhere did he pose a physical threat to warrant being flipped front-first onto his face, that's just appalling."

On Wednesday morning, NSW Police Commissioner Mick Fuller said the officer involved "had a bad day", but "not for one minute am I saying the officer's actions were correct."

"This is a case of two things - is it reasonable for someone to swear and threaten a police officer and, then, is the force the officer used reasonable?" Fuller said on 2GB radio.

"I don't know what happened before in terms of the lead-up, but there were probably other ways the officer could have dealt with that matter, no doubt."

NSW Premier Gladys Berejiklian said watching the video confirmed her belief "we still have a long way to go in our country".

"What happened in the US is a good wake-up call for all of us, and I think that all of us have our hearts breaking as to what's happening in the United States," she said.

"And we have to ensure that we can do what we can in our own country to protect all of our citizens."

'It happens in Australia too'.

From 1987-1991, Australia had a Royal Commission into Aboriginal Deaths in Custody. Many of its recommendations were never implemented, and at least 432 First Nations people have died in custody since, according to data collated by The Guardian.

The boy's family fronted media on Wednesday to discuss the incident, acknowledging it was taking place in a time where police brutality was front and centre following the death of unarmed black man George Floyd in Minneapolis, Minnesota.

Floyd's death has sparked protests and riots across all 50 states of America, plus around the world including London, Paris, Auckland and multiple Australian cities.

"What is happening is America has been happening in Australia for a very long time," the teen's sister, who has not been named at the family's request, said.

"We aren't inciting fear or violence by telling our stories, we are shedding the light again about the way Indigenous peoples are treated.

"This isn't the first time something has happened like this with our people. Maybe this time people will take listen and take action."

The father of the teen encouraged the family and supporters to 'take the knee' in solidarity with the Black Lives Matter movement and family of Floyd.

"What I want to do is acknowledge the George Floyd family, we are in solidarity with you and what's happening in America," he said.

"A prison that’s made up of the whole world".

The boy's family told media they felt angry, frustrated and afraid after watching the footage of his arrest.

"Because we're Aboriginal we see a lot of this all the time. We experience extra obligations to answer to people: who we are, where we're going, what we're doing, when we're just walking along," the boy's mother said, describing her son as a "typical teenager".

"I don't think he should be made to feel like he's in a prison that's made up of the whole world."

Speaking to the ABC, the mother said she felt her son's pain when she watched him fall to the ground.

"It wasn't my body that hit the ground, but I sort of imagined in my body what it would feel like," she said.

"It's not nice to see things like that happen to your children."

The father dismissed the police commissioner's claim the office was having "a bad day" in an interview with SBS News.

"Every day is a bad day for Aboriginal people," he said. "Every day, every year from year to year. We're struggling with mental health, we're struggling with unemployment... We're targeted for just being who we are.

"This has brought up a lot of anger and frustration because of what I had to go through [growing up]."

Family seeks prosecution.

George Newhouse, a lawyer from the National Justice Project, said the family would pursue a private prosecution against the officer if charges were not laid.

"The family want charges to be laid against this officer. Not an investigation where police are investigating police," he said at Wednesday's press conference.

"They've told me that if charges aren't laid quickly, we are instructed to launch a private prosecution. In addition, they want to know what's happening to the other officers that were present.

"There is a duty on officers to speak out. They don't want police investigating police. If this was anyone else, you or me or any member of the original community, we would be charged and let the court decide."

Read more:

• The fury in US cities is rooted in a long history of racist policing, violence and inequality.
• 'What every Australian needs to do in the wake of the Black Lives Matter protests.'
• 12 books to read about racism abroad and in Australia.
• "What would you do?" Nakkiah Lui has one question for all non-Indigenous Australians.
• Their names aren't trending on social media, but their lives mattered just as much.
• 400 deaths, zero convictions: Australia's national shame.

Feature image: SBS News/Facebook.