Three young Indigenous children are recovering with family after being cable-tied and forced to sit in the hot Broome sun as they cried and pleaded for their release.
Western Australian police have charged a 45-year-old man with three counts of aggravated assault in relation to the incident, which went viral on social media on Tuesday.
WA Greens senator Dorinda Cox described the footage as disturbing and confronting.
"We can never be okay with watching children as young as six being humiliated, their tiny wrists being tied up and leaving them crying in the hot sun," she said in a statement on Wednesday.
"Children are forever damaged by this type of behaviour.
"There is no justification for instilling terror into small children."
Police were called to the Cable Beach home on Tuesday, when a neighbour reported seeing kids swimming in a pool.
Ten minutes later police received a second call, from the 45-year-old man, telling them he had "restrained" three children for allegedly causing damage.
When they arrived, officers found two children - a six-year-old girl and a seven-year-old boy - had been cable-tied.
Police later found a third child, an eight-year-old boy, who had escaped.
WA Commissioner for Children and Young People Jacqueline McGowan-Jones told ABC Perth she was appalled after seeing the footage.
"It would appear these are very young and small children," she said.
"They appear to be quite frightened in the circumstances, he is quite a large man and they appear to be very nervous.
"These children are only six and seven, they don't have the neurodevelopment to understand cause and effect and consequences and actions and that is legally known."
Regional WA Commander Rod Wilde said children under 10 were not going to be criminally responsible.
"We're engaging with the children's parents," he said.
"They're certainly keen for the court process to run its course."
Senator Cox, a former police officer, called on WA police, politicians and the public to send a message that treating children so violently was not acceptable.
"As a mother, watching these children begging for their freedom and in fear was like watching a slow repeat of the historical racially based abuse experienced by previous generations of First Nations people," she said.
"We must confront such footage in the spirit of truth telling, however confronting this is ... as a community, we all have a shared responsibility to rise above and challenge abuse, violence, racism and attitudes that encourage these behaviours towards children."
Human rights lawyer and children's advocate Hannah McGlade said the incident showed vigilante-like behaviour directed at very young Aboriginal children.
"Aboriginal people do not feel that non-Aboriginal children would have been tied up and treated in such a cruel manner and that there is a racial element to this act," she said, adding it was rare that racially based matters were prosecuted in WA.
The Broome man was granted bail and will appear in court at a later date.
13YARN 13 92 76
Aboriginal Counselling Services 0410 539 905
Lifeline 13 11 14
Kids Helpline 1800 55 1800 (for people aged 5 to 25)