Detectives have been given another 36 hours to question a man from County Durham on suspicion of murdering his parents.
Police found the bodies of Bob Seddon, and his wife Patricia, at their home in Sale in Greater Manchester, on Friday.
Nic Seddon, 45, was arrested at his home in Seaham the following day. A post-mortem examination confirmed the couple died of gunshot wounds.
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The pair defrauded Durham County Council out of nearly £100,000 but were given suspended sentences.
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