Detectives searching for the body of Keith Bennett, one of the five victims of the Moors murderer Ian Brady, have been denied access to examine Brady’s briefcases and papers.

In the hours before his death in May 2017 Brady asked for two locked cases that were in his room at Ashworth hospital in Merseyside to be put in secure storage.

However, the day after his death a district judge at Manchester magistrates court refused to grant police a search warrant to open the cases on the grounds that there was no prospect of an investigation leading to a prosecution.

Keith’s brother, Alan, said requests made by the police and himself to Robin Makin, Brady’s solicitor and executor of his will, have also been turned down.

Brady and his accomplice, Myra Hindley, murdered Keith after abducting him when he was 12. They never revealed where he was buried.

Bennett said: “I am sure you will understand that there is a desperate need to look for anything that may help in the recovery of Keith’s body and there may be something in those cases.

“We cannot be sure [but] we need to know for sure – one way or another. During my correspondence with Brady many years ago he stated that he had left instructions in his will for me alone. He did not give any further detail but it was at a time when I was searching on the moor and asking him about routes taken, areas of the moor, landmarks.

“The refusal by Makin to help any further is a great cause of distress considering that my brother’s body still remains on the moor while all the other victims have been returned to their loved ones for a proper burial.”

Bennett claims Makin, Brady’s solicitor of 25 years, has told officers he could not open the two cases without a locksmith as he did not know the combinations.

Bennett’s solicitor, John Ainley, has written twice to Makin about the cases but received no response. Bennett personally wrote to Makin this year by letter and email but also got no reply.

“All this took place over a year ago and since that time he has ignored all further inquiries about access to the contents of the case. Those requests have been made by the police and a solicitor acting on my behalf,” added Bennett.

Brady tortured and killed five children with his partner Hindley in the 1960s. He was jailed for the killings of John Kilbride, 12, Lesley Ann Downey, 10, and Edward Evans, 17, in 1966. He went on to admit the murders of Pauline Reade, 16, and Keith.

The remains of three of his victims were found on Saddleworth Moor. The body of another was found at Brady and Hindley’s house.

Hindley died in jail in 2002, aged 60, after suffering respiratory failure following a heart attack.

A Greater Manchester police (GMP) spokesman said: “The application [for a search warrant] was made to a a district judge on 16 May 2017 and it was turned down. We did not proceed to the high court.”

Meanwhile, Martin Bottomley, head of GMP’s cold case unit, said detectives would never stop searching for Keith.

He added: “We will continue to do everything we can to pursue all investigative lines of inquiry to find Keith’s body, while also supporting his family and their efforts to uncover the truth. We will never close this case until we have the answers they so truly deserve.”

A spokesperson for Makin said he would not be making any comment.