The former teen inmate whose treatment in detention prompted the Northern Territory juvenile justice royal commission wants to shut down the Sydney Harbour Bridge and other national landmarks to protest against youth detention.

Ex-Don Dale Detention Centre detainee Dylan Voller has called for a national day of action held at CBDs in Brisbane, Perth, Adelaide and Alice Springs.

“Whoever wants to join us can shut down whatever they want to shut down – small towns, the big cities,” Voller said in a Facebook video that has since been deleted.

Dylan Voller testifies before the royal commission.

“I’d love to come over and lead the way, to shut down the Sydney Harbour Bridge just like we want youth justice prisons shut… they’re going to have to force us to move off that bridge.”

The 19-year-old said he wants the Australian public to stand together for the cause.

“Because our youth do matter and our youth are the future,” he said.

Footage of Voller being tear-gassed, spit-hooded and shackled to a restraint chair while behind bars was aired on national television last year, prompting Prime Minister Malcolm Turnbull to call the inquiry.

The commission is in its final week of hearings in Darwin before a report and recommendations are released on September 30.