A huge increase in the number of sex offences in Scotland has forced structural changes inside the country's biggest prison

An entire hall of Barlinnie in Glasgow is now needed to accommodate the prisons, with some claiming it is due to the effect on the confidence of victims coming forward after the revelations about historic abuse by TV presenter Jimmy Savile.

The police's Operation Hydrant into sex abuse inquiry is currently investigating 110 people in Scotland for offences, including 37 public figures.

In the past, sex offenders have been housed in special sections in jail because of the threat of violence and intimidation from other prisoners, who view perverts as the lowest of the low.

But the numbers have risen to such an extent - sex offenders now represent one in five prisoners at Barlinnie that E Hall is to be remodeled to take sex offending prisoners exclusively.

One source said: "There have never been more sex offenders inside Barlinnie than there are now.

"The courts are convicting men in large numbers, principally offences which are considered 'historical.'

"Victims are more prepared now to report offences of a sexual nature, even if they happened years or decades ago.

"This creates its own problems at Barlinnie. Not only are more men being convicted, many of them are elderly and have greater medical needs than younger prisoners."

The total number of inmates at Barlinnie currently stands at 1200, well down on the 1700 who were banged up there just a few years ago.

But while overall numbers have fallen, the ratio of sex beast has increased rapidly. E Hall has 180 cells, accommodating 265 prisoners.

But 240 of them are sex offenders, forcing the prison authorities to allocate them one of the prison's six halls exclusively.

Crime writer Robert Jeffrey, who wrote a book on Barlinnie, said most mainstream prisoners said: "Not so long ago, some cons considered it almost an obligation to make life difficult for sex offenders, attacking the 'beasts', as one long-time con described it to me.

"Today, things are in my view marginally better, thanks to education, but mixing both sets of prisoners is still fraught with danger."

Elaine Murray, the shadow minister for community safety, said: "Underlying the rise is evidence of a sea change in the way sex offences are considered by the authorities."