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.
More top news
Veterans, cadets, dignitaries and serving Northumberland Fusiliers have paid tribute to those killed at the Battle of the Somme
Clear spells. Showers. Brisk winds. Sunday looks like the better day
Two men whose grandfathers fought in the Tyneside Irish battalion and died together on the Somme have returned to visit their graves.