Catholic agency Caritas Australia has welcomed Australian Prime Minister Malcolm Turnbull's announcement that a Royal Commission will investigate evidence presented in an ABC Four Corners program concerning the detention of juveniles in the Northern Territory.

Mr Turnbull made this announcement on Tuesday morning, saying the issues raised on the program - which showed footage of prison guards tear-gassing six boys being held in isolation in a Darwin detention centre in 2014 - needed a "thorough inquiry". "Like all Australians, I have been deeply shocked - shocked and appalled, by the images of mistreatment at the Don Dale Centre," he told ABC radio.

Paul O’Callaghan, CEO of the international aid and development organisation which has worked with Indigenous Australians for more than 50 years, described the images shown in Monday night's program as "profoundly disturbing" and said they were "not representative of a country with values such as ours, particularly to those who are most vulnerable, such as children in detention".

“Every child in Australia is entitled to be treated with dignity and the Australian Government is obliged by its commitment to international conventions, to ensure that systemic abuse of children does not occur in this country," he said.

Noting that Aboriginal children make up almost 60 per cent of those in juvenile detention in Australia and 96 per cent of those in juvenile detention in the Northern Territory, Mr O'Callaghan said he expected the Australian Government to act promptly in establishing the Royal Commission. 

Caritas has called for the terms of reference to cover all jurisdictions and to examine the success of alternative approaches to the detention of children, including so-called 'restorative justice' approaches.

Mr Turnbull said the Royal Commission would be held jointly with the Northern Territory Government.