A HELENSBURGH sex beast who filmed himself raping a five-year-old girl has been told he will be in prison until "there is any hope of him not being a danger to young girls".

William Rigby, 53, preyed on the child while he was baby-sitting her on October 11, last year, at a house in the town.

At the High Court in Glasgow this morning (Tuesday), Rigby was sentenced for sexually assaulting and raping the child and for earlier abusing two other girls.

Judge Lady Stacey placed Rigby on an order for lifelong restriction - similar to a life sentence – and ordered that the punishment part should be seven years.

But, she told him: “That does not mean you will be released then. It may be you are never released.

"You will be in prison until there is any hope of you not being a danger to young girls.”

READ MORE: Helensburgh child rapist filmed himself abusing five-year-old girl

Lady Stacey added: “You are guilty of a horrible catalogue of offences. What you did was betray the trust of a family and what you did harmed these children.

“You present a risk to the public and are likely to continue to do so even after work is done with you."

As Rigby was led away to the cells, a relative of one of his young victims shouted "die” at him.

The court heard earlier that the sobbing young girl who was raped told her mother what had happened when she returned home around midnight.

When the mother confronted Rigby, he claimed that the child had misunderstood what had taken place.

He left the house after stating to the woman: “I am sorry if she misunderstood what happened.”

Rigby, however, was later held by police. His mobile phone was seized and a series of sick video clips of him with the girl were found.

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Prosecutor Margaret Barron told the court this included him raping the child, who was in her pyjamas at the time.

At one point, Rigby asked the girl to say “hello” to the camera.

A further 34 indecent images of children were also discovered.

Rigby later told police that he should be “punished” for what happened.

A probe revealed he had preyed on two other girls between 2006 and 2018.

One was aged just four when the abuse began, while the other was six.

Rigby insisted with one of the victims he had acted on “impulse”.

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He admitted to charges of indecent and sexual assault in connection with these girls.

Solicitor advocate Douglas Thomson, defending, said: “He now recognises there was manipulation of the children and his actions will have consequences for them for many years to come.

“When he is released into the community, if ever, he will be monitored and subject to the most stringent conditions.”