Body parts and tissue of soldiers killed in Afghanistan have been kept by the Ministry of Defence without the permission of their families, officials have admitted.
Some six body parts and more than 50 tissue samples were retained by the Royal Military Police without relatives of the servicemen being notified.
The remains were discovered last month when a new manager was appointed at the Military Police's Special Investigations Branch (SIB).
Officials are trying to identify and inform the families affected while an urgent investigation has been launched, an army spokesman said.
The body parts were reportedly found at the John Radcliffe Hospital in Oxford, while the tissue samples - which were kept on laboratory slides for matching or identifying the dead soldiers - were discovered at the SIB's headquarters at Bulford Garrison in Wiltshire.
It is believed that because multiple samples were taken for each case, the number of families affected is likely to be less than 60.
The army spokesman said: "There are occasions when it is necessary for the RMP Special Investigations Branch to retain slides of forensic material from individuals killed on operations as part of their investigation - this is standard practice.
"However, the RMP identified there were a small number of cases where this had been done without the correct processes being followed to inform families.
"It is thought there could be 60 forensic items, such as microscope slides, containing material from some individuals."
He added: "Investigations are being carried out urgently into this matter. The RMP Special Investigations Branch has also taken swift action to ensure this cannot happen again and are identifying the families affected as quickly as possible."
The MoD said approximately 90 per cent of the 60 forensic items were histology slides.
It said a change in the way the SIB liaised with families was to blame for the consent not being achieved, adding that when the oversight came to light in July procedures were immediately changed.