LONDON (AP) — Britain's Ministry of Defense has admitted it kept body parts and tissue samples from dead soldiers without notifying their families.

The Military Police's Special Investigations Branch routinely keeps slides of forensic material — with families' consent — from British troops killed in operations in places such as Afghanistan to aid in investigations.

The defense ministry said Thursday it is urgently investigating how in a "small number of cases" body parts and forensic material such as microscope tissue slides were retained without following procedures to inform families.

It said there could be 60 "forensic items" involved.

The ministry blamed the mix-up on a change in the way military investigators liaised with families and said it is working to identify affected families as quickly as possible.