Riot squad called in to control unruly and unsupervised teens on Rottnest Island

The riot squad has been sent to Rottnest Island, off the coast of Perth, to control hundreds of unruly and unsupervised high school students, some as young as 13. 

Police are investigating a series of assaults, including on a father who was holidaying with his young family.

Unofficial end of school celebrations left dozens of visitors shaken and police frustrated as aggressive and abusive teens fuelled by alcohol harassed families.

"My nine-year-old was crying, ringing her bell and they were shouting at her, 'F--- off little girl, keep riding your bike'," Isaac said. 

He was left bloodied and bruised by his run-in.

"I went up to this group of boys and said, 'You can't talk like that to anyone. That's my wife and daughter there'," the father said.

"And then that's when they sort of got around me and started hitting me from behind and that's when I fell over and came off second best."

"Juvie week" is an unofficial end-of-school celebration for private school students in year 11 and below. 

Revellers described the celebrations as being like the underage version of Leavers – Schoolies in the rest of the country – and "just having fun after school finishes", but some took it too far.

A party at The Basin, a popular swimming location, ended in brawls and two police were hit with bottles.

The riot squad and Air Wing were both called in.

"Junior Leavers has become a developing issue over the past three years," WA Police Superintendent Dave Dench said.

"The increased police presence this year was as a result of some issues that occurred last year.

"But certainly what happened over this weekend is the worst it's been so far."

There were also reports of teens attempting to break into resorts and stealing bikes.

The Rottnest Island Authority told 9News there was increased CCTV and police presence at these busy times. 

"Minors are not permitted to be left unaccompanied on the island and this is clearly communicated to our guests," a spokesperson said.

" … Everyone has a role to play in maintaining a safe and family friendly Rottnest Island." 

Dench said the problems were "very frustrating" and could easily be avoided by "parents taking responsibility for their children and not leaving them unsupervised".

A number of arrests were made but as of tonight no charges had been laid.

Visitors and staff told 9News the behaviour had never been this bad.

With a few more days of celebrations to go, police said resourcing for next year would be reviewed to ensure safety.

Tonight there were at least three additional officers on the island in case things got out of hand.

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