A 45-year-old was arrested on suspicion of murder in the North East on Saturday after a man and a woman in their 60s were found dead in a house in Sale, police said.
The couple are thought to be Bob Seddon, 68, and his wife Patricia, 65, according to the Manchester Evening News, but the bodies have yet to be formally identified.
A Home Office post-mortem examination revealed that both had died from gunshot wounds.
The arrested man remains in police custody for questioning.
Superintendent Simon Retford, based at Stretford, said: "We have launched a murder investigation to establish the exact circumstances of what has happened here and why. Our investigation will be able to find the answers if it is allowed to run its natural course unhindered by speculation or gossip.
He continued: "People need to trust the police to continue with their investigation. What I can say is that there is no evidence whatsoever that anyone else in the community has ever been under any threat from this incident. What happened appears to be isolated but this is a dynamic, fast-paced investigation and we are not leaping to any conclusions. The fact remains that there has been a double tragedy and our thoughts are with the families affected at this terrible time."
Supt Retford assured that more police will be patrolling the Sale area and that should residents have any queries, they should not hesitate to approach police and ask.
Officers from Greater Manchester Police found the bodies at Clough Avenue after being called at about 4.35pm on Friday.
The couples next-door neighbour Duncan Statham, 53, told Manchester Evening News: "They were fantastic people, they’d lived here for years and were always so kind with my kids and other kids on the street.
"It’s a massive shock. They were such an ordinary, down-to-earth couple and you could never see them being involved in something like this. My heart just goes out to their family – we know them well and they are such a nice, unassuming family and I’ve no idea what they must be going through."
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