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Police appeal for witnesses in MI6 murder case

6 September 2010 Last updated at 15:31 BST

Scotland Yard has released new CCTV images of Gareth Williams, the MI6 worker whose body was found in a padlocked bag in his London flat.

Detectives say he was unclothed - and a post mortem examination has revealed no trace of alcohol or drugs. The senior investigating officer, Detective Chief Inspector Jacqueline Sebire, has appealed for two potential witnesses to come forward.