A rapist who indecently assaulted three schoolgirls over a period of two decades has been jailed for 21 years.

The youngest victim of Derek Osborne, 72, was just four when he sexually assaulted her.

He will have to serve at least 14 years of his sentence and could die in prison, Ipswich Crown Court heard.

Jailing the former Sizewell B worker, Judge John Holt said Osborne's victims had all suffered 'devastating' psychological effects.

He said a probation officer who interviewed Osborne, formerly of Pakefield, near Lowestoft, had assessed him as 'dangerous' and said he had shown 'very little' genuine remorse.

Judge Holt said Osborne would have to serve at least 14 years before he could be considered for release by the parole board and he would only be freed when he was no longer considered dangerous. On his release, he will have an extended licence period of five years.

Osborne admitted 16 offences between 1982 and 2004, including eight of indecent assault and seven of indecency with a child – relating to three schoolgirls. He also admitted raping a woman.

The court heard Osborne had offered one of his victims money to perform sex acts on him and had lost his temper with another, when she refused to do what he wanted.

He had sexually assaulted one of the girls after making her watch pornography and when she was eight or nine he had made her dress up in women's underwear.

The offences came to light when one of the victims confided in her partner and he got her to contact the police.

When he was arrested, in February last year, Osborne denied all the offences and claimed one of the girls had made sexual advances towards him.

Neil Usher, for Osborne, said: 'There is every likelihood that he will die in prison.'

He said, recently, Osborne had been living in a bedsit in Blackpool and he was unlikely to reoffend. 'He has no sexual urges whatsoever,' said Mr Usher.

After the sentencing, one of Osborne's victims, a woman in her thirties, who cannot be named for legal reasons, described his sentence as 'amazing' and said she had been worried he would only be jailed for a couple of years. She was four when he sexually assaulted her and only realised what he had done was not normal when she saw a TV programme on sex abuse when she was 10.

She said she was not surprised to hear Osborne had not showed any real remorse.

'If he couldn't show any compassion or remorse to a young child, why would he show remorse now?' she said.

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