Demonstrators turned out in cities across Australia yesterday to protest against the abuse of indigenous boys in juvenile detention in the Northern Territory. Video film and images similar to that of prisoners in Abu Ghraib showed children being stripped, tear-gassed, hooded and cuffed to chairs.

Footage of the abuse first emerged on national broadcaster ABC's Four Corners programme. Filmed at the Don Dale youth detention centre in Darwin it focused on the treatment of Dylan Voller, who was assaulted, stripped naked and kept in solitary confinement, aged 13 and 14.

At one stage he was strapped to a restraint chair while wearing a hood for almost two hours. He was also among a group of six children who were subdued with tear gas.

After the programme aired Prime Minister Malcolm Turnbull announced a royal commission into the abuse. However he rejected calls for a broader national inquiry.

However, Aboriginal and Torres Strait Islander lawyer Matthew Bonson hit out, saying: "The NT (Northern Territory) government ... is part of the problem and cannot be trusted to investigate themselves". He also added that the royal commission needed to take "a forensic look into racism and outdated, closed-minded attitudes in addition to child protection, detention, health and welfare".

Opposition Leader Bill Shorten offered his unwavering support for a royal commission into the claims and called for the Prime Minister to appoint two indigenous co-commissioners. "My vision of Australian justice is not to see a 14-year-old boy hooded, restrained and strapped to a chair," he said yesterday.

The United Nations Human Rights Commission also said it was shocked by the footage. In a statement it said: "We encourage the Government to extend the scope of the investigation...to establish that such appalling treatment is not taking place in any other place of detention in Australia."

The six boys featured in the abuse documentary are seeking damages for mistreatment, according to ABC.

Indigenous people represent about 3% of Australia's population but are 26 times more likely to be in detention than non-indigenous youth, according to the Australian Institute of Health and Welfare.

The rallies, held in capitals and major cities country-wide on Saturday, also touched on a lack of indigenous consultation over the royal commission's terms of reference.

Protests in Melbourne shut down traffic outside Flinders Street Station as some demonstrators sat in a make-shift cage.

Cries of "shame, shame" were heard in Adelaide, as others gathered at Brisbane's Queen Street Mall and on the front steps of Sydney's Town Hall to voice their concerns.

The Townsville Human Rights Committee expanded its protest to cover Australia's offshore detention programme where migrants are held in camps.

"All forms of abuse against children is a breach of their human rights," it said in a statement.