Body parts of Harold Shipman's victims were kept by police for more than ten years before they were secretly destroyed without the families' permission Police kept body parts from 12 women after exhuming them in the late 1990s Remains put in an incinerator and burned without ceremony in 2011 Officers only bothered to tell the victims' families after a local newspaper reporter was tipped off about what happened Police said they 'agonised' over what to do with the remains for months Shipman killed between 215 and 260 people over a 23-year period Serial killer: Harold Shipman murdered between 215 and 260 of his patients using the drug Diamorphine over a period of 20 years Human remains from some of serial killer Harold Shipman's victims were kept for more than a decade by police before they were secretly destroyed without the families" permission, it has emerged. The samples were taken from 12 women to establish cause of death, police said. They were kept in storage for a number of years to ensure that police had the appropriate evidence should the murderer or his family appeal against his conviction. But in 2011 police decided to 'respectfully dispose' of the tissue samples without telling the families. The remains were taken to an incinerator and burned on February 16, that year, without ceremony. Police only told the victims' families what they had done recently when they realised a local newspaper reporter had found out about it. Greater Manchester Police chief constable Sir Peter Fahy said officers 'agonised' over whether or not to tell the families but decided not to, to save them reliving 'upset and distress'. The remains belonged to Kathleen Grundy, Joan Melia, Winifred Mellor, Bianka Pomfret, Ivy Lomas, Marie Quinn, Irene Turner, Jean Lilley, Muriel Grimshaw, Alice Kitchen, Elizabeth Mellor and Sally Ashworth. Their bodies were exhumed during the Shipman investigation in the late 1990s. Sir Peter Fahy said: 'This was not a decision that we took lightly, in fact it was a decision that we agonised over for a number of months with a number of independent advisory groups, partner agencies and other professionals. Victims: The remains which were incinerated belonged to (clockwise from top left) Norah Nuttall, 65, Jean Lilley, 59, Marie West, 81, Bianka Pomfret, 49, Joan Melia, 73, and Kathleen Grundy, 81 Victims: The other six people the remains belonged to were (clockwise from top left) Irene Turner, 67, Lizzie Adams, 77, Winifred Mellor, 73, Pamela Hillier, 68, Kathleen Wagstaff, 81, and Maureen Ward, 57 I would hope that the public would understand that this was a very difficult decision for us to make but I want to assure people that we made this decision for the right reasons. It was never our intention to cause the families any pain or distress. These families had not only experienced the upset of losing a family member but had had to relive it in the glare of the media and the public time and time again - that is something that most people will thankfully never have to experience. 'A number of years had passed since the trial and Shipman's death and was it right for us to cause even more upset and distress by making the families relive this yet again? No part of any murder investigation is simple and every decision is made with the best of intentions; how much should we tell families? How much do they want to know? The facts of any such case are distressing enough but do we add to this with even more detail? These are questions that officers are faced with on a daily basis. Appeal: Police kept the remains in case Primrose Shipman, the wife of the serial killer, decided to appeal against his conviction years after his death Victim: The grave of Kathleen Grundy (left) who sparked the murder investigation. Her daughter went to police after Mrs Grundy's will was altered in favour of Dr Shipman. The probe uncovered a number of suspicious deaths. Pictured right is Joe Kitchen, the son of Alice Kitchen, who was a victim of Dr Shipman As soon as we knew that a journalist had become aware of this, specially trained officers visited all of the families involved and fully explained our rationale which they all took on board and fully understood. We now continue to support these families as they are now forced to relive the hurt and upset yet again. Shipman, the UK's most prolific convicted serial killer, was jailed for life in 2000 for murdering 15 patients using the drug Diamorphine while working in Hyde, Greater Manchester. Nine of these victims were exhumed and three other victims who were not in the court case also had their remains dug up. Police said that some human tissue was retained as evidence until a meeting in October 2007 when they decided to hold on to the samples for another five years, in case of any further legal challenge by Shipman's widow Primrose. The decision was reviewed in 2010, after the Association of Chief Police Officers asked all police forces to conduct an audit of human tissue in storage in the wake of the Human Tissue Act. A force spokeswoman said that since there had been no legal challenges, the decision was taken to 'respectfully dispose' of the human tissue in February 2011. An inquiry concluded he killed between 215 and 260 people over a 23-year period in Hyde and Todmorden, West Yorkshire. He committed suicide in January 2004.