Back in Brisbane, no one is in any doubt that British children will now be in danger from Horne. But he is likely to be provided with a home paid for with housing benefit, given help to find a job ? and even given special protection.

Horne is expected to be made the subject of sexual offences prevention order, which applies to an offender convicted overseas who poses a risk of serious sexual harm in the UK.

It can prohibit him from being alone with children or from being within a certain distance of a playground, for example.

But he is not kept under constant supervision, and authorities in the field of child abuse say the move to have him repatriated where he has no family or network of friends could have devastating consequences for vulnerable youngsters who may cross his path.

Even his prison doctor, Wendell Rosevear, who supervised him during his 12-year sentence for raping two teenage boys, said: “The risk of paedophiles re-offending is known to increase after deportation, due to heightened anxiety. I fear that British children will be at risk after he settles into the wider community.”

Professor Freda Biggs, of the Australian group Advocates for Survivors of Child Abuse, added: “There are child-sex offenders who should never be released ? and he’s one of them.

“I’m delighted there’s one less paedophile in the country. But someone’s child, somewhere, is going to pay for this.”

Representatives from agencies tasked with monitoring him spent yesterday making sure arrangements were in place for his supervision. But he is under no legal obligation to co-operate with them because he is not subject to parole.

Horne is part of the Multi-Agency Public Protection Arrangements (MAPPA) scheme, which means he is monitored and supported by several agencies ? paid for with taxpayers’ money.

A Ministry of Justice spokesman said: “Normally when sex offenders are released, they are on licence and can have conditions attached to this, such as to live in a certain address or be banned from certain areas.

“In a situation where a sex offender returns from a foreign country, this does not exist, so there are no legal requirements to adhere to.

“Initially part of the risk management would be to put together a plan that the offender will comply with. But if they decided the best thing would be for the offender to live in a certain place, for example, then there would be no way of making him do that.”

One of the first things Horne will be encouraged to do is change his name and alter his distinctive appearance, which has been likened to Father Christmas.

There are concerns that his white hair and beard, coupled with his Australian accent, mean he is easily identifiable and therefore vulnerable to vigilante attacks.