A 13 year-old Indigenous boy was hospitalised and required surgery after being mauled by a police dog in Perth over the weekend.

The boy and his friends were in St James in Perth's south east Sunday night and ran when they saw a police vehicle.

When Jayden stopped running, he was bitten repeatedly by a police dog. It has been alleged he was cuffed when the dog attacked him, and that he was kicked by a police officer.

WA Police deny both allegations but confirmed he was bitten and wounded by the dog.

Jayden suffered lacerations to his face, neck and arm, and a broken nose.

Jayden's grandfather Elder Abraham, 72, has been by his side and stayed with him at Perth Children's Hospital every night since the attack.

"I feel terrible to see him like this. He is still in pain and in shock. He has needed quite a few stitches," he said.

"This is the way police treat the Black kids. They do anything they want when dealing with Black children."

Mr Abraham, who was visibly distressed when speaking on Wednesday, said his grandson had surgery Monday night around his eye and reconstructive surgery to his arm where tendons were damaged.

"We need the body-worn camera video released," he said.

Jayden's grandfather, Elder Abraham, and Mervyn Eades outside Perth Children's Hospital.

Noongar community advocate Mervyn Eades said there were incidents reported in the area but Jayden was not involved in them.

Mr Eades said the boy had not been charged with any offence, has no criminal record, and was not carrying a weapon.

"Jayden was not involved in any crime. Our children get scared when they see police. Their automatic reaction is to run," he said.

Mr Eades said fear of the police was entrenched in the Aboriginal community.

"It takes a lot out of our Elders. Our nans and pops are the backbones of our families and they have seen this for 70 years of their own lives," he said.

"Would this have happened to a non-Indigenous child? It is systemic racism. This little boy just turned 13.

"He would be traumatised by seeing police all the time now. Whenever he sees police, he will be wondering what is going to happen next."

Mr Eades said all available video of the incident must be made public.

"We have been told there will be an internal investigation and the CCC is looking at it," he said.

"The video must be released as soon as possible otherwise it gets swept under the carpet. If we don't see it and they tell us there is nothing to see, how can we believe that?

"It was really brutal brother, to be quite honest, it was excessive. The kids who saw it said he was in cuffs."

Mr Eades said he, along with advocate Megan Krakouer and Jayden's family, had met with the superintendent of Cannington police station at the hospital.

WA Police Deputy Commissioner Kylie Whitely said on Wednesday morning that the incident is under investigation.

"Police were responding to around 10 calls in St James and Bentley, reports that vehicles and homes were broken into... also reports of individuals being threatened," she said.

"The police dog was deployed... and effective in making a number of arrests. During that incident there was a juvenile bitten by the police dog who has consequently undergone intervention in hospital... Our primary concern at the moment is he is given the appropriate support in hospital."

The deputy commissioner said the police had been deployed in the appropriate way.

"We will, of course, review the deployment of the dog, the use of force, and the actual outcome of that incident," she said.

"We will continue to interview individuals and will continue working with the family."

Deputy Commissioner Whitely said the body-worn camera footage does not support the allegation Jayden was cuffed when attacked by the dog, or that he was kicked by an officer.

One of Jayden's injuries. Photo provided by the family.

In an earlier statement, WA Police said Cannington Detectives were investigating a series of incidents that occurred in the Bentley/St James area on Sunday night.

"Police deployed a number of resources to the area, including canine unit, and located an adult male and three juveniles about 11:40pm on Stannard Street in Bentley.

"All four were taken into police custody. One of the juvenile males received injuries during the arrest, as a result of canine deployment. He was conveyed to Perth Children's Hospital for treatment of the injuries."

The statement said a 21-year-old male was charged. There were no charges against the three juveniles.