Detectives investigating the Jersey child abuse scandal expect to arrest three suspects in the next two weeks, despite attempts by “corrupt former cops” to block the inquiry.

One of the three suspects lives in mainland Britain.

Before announcing progress in the inquiry yesterday, Deputy Chief Officer Lenny Harper said he had been facing sustained obstruction from retired officers trying to cover up their own failure to investigate complaints of abuse at Haut de la Garenne, the former children’s home.

Yesterday several hundred residents demonstrated in St Helier in sorrow for the victims and anger at what they called Jersey’s “culture of secrecy”.

Harper later confirmed that blood found in a concrete bath in a basement room was human and would be sent to a laboratory for DNA tests.

Search teams will move into a second underground chamber tomorrow following the completion of forensic tests in the first basement room.

Harper also said he had received increasingly disturbing stories of abuse alleged by former inmates. He said one of the incidents is likely to have led to the victim’s death. “There is one particularly graphic account that still causes us concern,” said Harper. “You would have to think there’s a strong possibility that the person died.”

Witnesses reported to his officers that the child concerned was “never seen again”. It is understood this case related to abuse in the 1970s.

Other accounts given by victims which Harper described include children being forced to watch acts of sexual abuse against fellow residents.

Separate from the Haut de la Garenne allegations, one victim claimed to have been sexually abused as a child during a trip with the Jersey sea cadets to the River Thames. About 100 victims’ accounts relate to Haut de la Garenne, while another 60 claim to have been abused elsewhere on the island. There are believed to be about 25 suspects in the Haut de la Garenne inquiry.

Asked whether there had been pressure to limit the scope of his investigation, Harper, who is from Northern Ireland and has served in Jersey for almost six years, said: “There has been stacks of it. Mainly from ex-cops, corrupt cops who have got friends in among senior politicians on the island. I would not insult the island by saying there is a culture of corruption; there is a cache of corrupt ex-coppers.”

Harper said the campaign against him had intensified since the discovery of part of a child’s skull at Haut de la Garenne brought the inquiry to widespread attention last month.

“There were calls made and anonymous e-mails sent to national newspapers in the past week warning them not to trust the chief officer and myself, and that definitely came from the sister of one of the corrupt cops.”

He added: “There is no doubt allegations were made by children in the past and they were simply not dealt with the way they should have been – that includes the police, the social services and everyone else. British police have been invited to Jersey to support this work.”

Harper, 56, said the attempts to block his investigation arose from an earlier attack he had mounted on police corruption. He was responsible for sacking a “hard core” of officers who had allegedly demanded sexual favours from members of the public and taken holidays paid for by Jersey businessmen.

He said the former officers – including one high-ranking policeman – threatened him when it became clear his child abuse inquiry would expose their failure to investigate. “I received about 140 abusive letters with threats to burn my house and my car,” said Harper. “This happened about a year ago.”

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