Police are preparing to hunt for a second network of cellars at a Jersey children’s home at the centre of allegations of sexual and physical abuse.

Specialist search teams hope this week to complete their examination of an underground room they found at the Haut de la Garenne home in which former residents claim to have been brutalised.

The activities of more than 40 suspects are being monitored by police as detectives confirmed they had received complaints of abuse that allegedly took place only months ago.

A police spokesman said: “There was an offence committed late last year which is being dealt with. It is not related to offences committed at [Haut de la Garenne].”

Investigations into claims of abuse started in 2003 when a former resident of Haut de la Garenne, which closed in 1986, was convicted of blackmailing a care worker by threatening to expose him as a paedophile.

The investigation has been widened to include the island’s Greenfields Secure Unit and the Sea Cadet force which used Haut de la Garenne. More than 200 alleged victims and witnesses have contacted police about alleged abuse from the 1960s to 1986.

The first underground chamber to be uncovered at Haut de la Garenne is a 12ft square room containing a 5ft-deep communal bath. A pair of shackles were also found in the room.

Detectives exploring the cellar hope later this week to break through to an adjoining chamber which has a bricked-up doorway.

Former residents have told detectives that the cellar complex, referred to as “Baintree”, was used to punish misbehaving children. Victims have described being lowered into a “deep, dark pit” where they were left with other children in a large bath of cold water before being abused by care workers and outsiders.

Police believe that a similar-sized underground complex could also exist in Haut de la Garenne’s north wing, close to where a piece of child’s skull was discovered last month. Detectives are reviewing the discovery of other bones at the spot in 2003 which were thought to have come from an animal.

They will also investigate an underground storage area close to the building’s swimming pool and two 3m-deep pits in the courtyard. Detention cells in which former residents claim that they were abused in the main building will be examined as well as the newer Aviemore wing.

A leading member of Jersey’s political establishment was confirmed by police yesterday as among those named as an abuser. Wilfred Krichefski, a senator in Jersey’s government and chairman of several committees, allegedly regularly visited Haut de la Garenne to abuse boys until his death in 1974. Living members of the island’s establishment, who cannot be named for legal reasons, have also been identified as suspects.

One former resident has claimed he was repeatedly raped at the children’s home by Krichefski between 1962 and 1963. The man, now in his late 50s and living in the West Midlands, said that every month he and another boy would be taken into a back room at the home and abused by two men.

The former resident said he would be woken by a care worker with the words, “There is someone here to see you.” The only person he told about the abuse was a psychiatrist who told him he would be placed in a mental hospital if he repeated the allegations.

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