The grisly secrets of an island long haunted by suspicions of child cruelty were being dug up yesterday by police officers who have found one child’s skull and are now searching for other remains in the cellars of a former children’s home.

The holiday isle of Jersey is having to face up to its past as police investigate an alleged culture of Establishment cover-ups after being told that children who died in care were formally reported as runaways.

After the discovery of the skull buried in a Victorian-built institution used as a location for the television series Bergerac, officers searched the area with sniffer dogs. They have identified six more sites of interest at the hostel and say they cannot rule out the discovery of more bodies.

The child’s skull unearthed over the weekend has been sent to the mainland for dating but police say that it had been there for at least five years. Police used dogs and ground-penetrating radar to uncover the remains, which were under 7in of concrete.

The discovery is a bleak vindication for a health minister who was sacked after raising concerns about systematic cruelty to children in care.

A 12-month covert police investigation into child abuse going back several generations began on Jersey in November 2006. It was made public a year later.

“Police officers became concerned at the number of people in positions of authority who were being connected with paedophile crimes,” Lenny Harper, the island’s deputy police chief, said. “We don’t yet know how this child came to meet his or her death. We can’t say that it was a homicide but have to treat it this way. Much of the information we are receiving leads us to this fear.”

Jersey is an island of secrets. Under Nazi occupation, its Government passed anti-Jewish laws and, although individuals acted bravely to save lives, there was no effective resistance. The island’s economy has become dependent on the secretive business of offshore banking, although it now co-operates with law enforcement agencies overseas.

The States of Jersey police force, which is investigating the rumours of child cruelty, is led by outsiders. Mr Harper is an Ulsterman; Graham Power, the chief officer, is a Yorkshireman; and Alison Fossey, head of family protection, is from Glasgow.

The force decided to base its child-abuse hotline in the United Kingdom so that callers could be confident that their testimonies would be shielded from fellow islanders. Already 140 potential victims and 40 suspects have been identified by police.

Although the investigation began with claims of abuse involving the Sea Cadets, it has moved on to focus on care institutions. The imposing Haut de la Garenne home was built in 1867 as the Industrial School for “young people of the lower classes of society and neglected children”.

By the postwar era it was a children’s home. In a practice that continued on Jersey until recent times, vulnerable orphans and children whose parents were unable to cope had to live alongside child criminals.

Stuart Syvret, the island’s former health minister ousted last year after protesting about harsh punishments in a children’s home, has met residents of that institution from the 1960s. One was a man who recalled harsh canings, beatings and solitary confinement by some staff for minor misdemeanours. In 1966 a 14-year-old boy hanged himself from a tree to escape the regime.

A woman who worked in the kitchen at another children’s home in the same parish in the 1980s said: “We had no idea any of this was going on, though a lot of people must surely have known. It seems scarcely credible that a child could vanish on an island the size of Jersey without anyone noticing or asking questions.”

More recently a social worker from Britain was sacked after revealing that confinement was being used in a Jersey children’s home in 2006.

An independent inquiry into childcare was ordered by the island’s Government last year.

Last month a 76-year-old man became the first person to be charged in the investigation. He was accused of indecently assaulting three girls aged under 16 between 1969 and 1979, when they were at Haut de la Garenne.

Frank Walker, the Chief Minister, expressed horror at the discovery of a child’s remains. “It is imperative that our children are safe in Jersey and I believe that today they are,” he said. “It is, however, clear that this may not always have been the case . . . we will do everything in our power to assist the police in seeking out the person or persons responsible.”

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