More than a decade of systematic and brutal abuse of vulnerable children can today be revealed for the first time after a three-year media blackout was lifted.

More than a decade of systematic and brutal abuse of vulnerable children can today be revealed for the first time after a three-year media blackout was lifted.

Three members of staff at the Norfolk special school at the centre of the biggest child cruelty investigation in the county's history have been convicted of a string of offences of ill-treating and assaulting young boys. Other charges of sexual attacks were formally withdrawn at Norwich Crown Court.

Over 30 years, hundreds of parents trusted their children to the school's care - assured by the authorities that it was the ideal establishment for their development and welfare. During that time millions of pounds of public money funded the school which operated under a “climate of fear”.

Among those convicted was George Robson, owner and founder of Banham Marshalls College, formerly the Old Rectory School, near Diss. He hid the cata-logue of maltreatment beneath a veneer of respectability as he was feted by royalty and former prime minister Tony Blair.

During the trial it was said the defendants carried out “deliberate acts of cruelty” including beatings which went far beyond even the strict standards of corporal punishment.

Police and council officials have launched a hotline to encourage further abused pupils to come forward amid fears countless more will never find justice. The litany of offences included:

t Pupils being encouraged to fight each other while goaded by members of staff.

t A boy being forced to eat his own vomit and others being beaten with a plimsoll and a studded belt.

t One child was forced to smash his new toys with a hammer after damag-ing a piece of furniture.

George Robson, 66, of The Street, Bridgham, was found guilty of nine counts of child cruelty. Until yesterday the convictions could not be reported as he faced trial for two charges of indecent assault. These were withdrawn after the court considered reports from a cardiologist and neourophysician saying he was not fit to stand trial.

His brother Anthony Robson, 63, of Mill Road, Banham, known as Tony Thomas to pupils, who was head of childcare at the independent residential school, was convicted of three offences. Care worker David Clarke, 56, also of Mill Road, Banham, was found guilty of four counts.

Leslie Beckett, formerly of Harleston, faced possibly the most serious case as he was charged with 13 counts of indecent assault but he died before he could be brought to trial.

There were 12 victims in total whose cases were successful. They were all male and included many from Norfolk and others from around the UK who attended the school from 1975.

Norfolk County Council moved to reassure parents that procedures are now in place to prevent a recurrence of such violence. Director of children's services Lisa Christensen said that safeguards were now in place to prevent the recurrence of such crimes.

She added: “Violent and cruel behaviour against children is never acceptable or defensible and is made even worse when it is handed out by people specifically entrusted by society with the daily care and welfare of other people's children.”

Det Insp Matt Sharman who led the inquiry said the victims were deeply affected by the abuse. While some have gone on to lead successful lives others have never recovered.

“This has been a long and involved investigation looking into events that took place up to 30 years ago,” he said. “The many victims in the case, some of whom had never come to terms with what happened to them at the Old Rectory or Banham Marshalls College, were traced to addresses all over this country and even abroad.

“The school was clearly run in a climate of fear with 'control' of the children being of paramount importance. Even in the days when corporal punishment was still legal, the events at the school went far beyond what was acceptable, particularly to vulnerable children.”

Clarke has already been sentenced to a 12 month suspended sentence. George and Anthony Robson will be sentenced in coming weeks and could face ten years in jail. Two other men - Robert Wilson and Derek Holesworth - were cleared of all accusations of child cruelty.

Banham Marshalls is now under new ownership and is called Eagle House School. The school is a day and residential school for young people with autism. There are no concerns over child welfare under the new management.