A 45-year-old man has been arrested on suspicion of murder after a man and a woman in their 60s were found dead in a house, police said.
Officers from Greater Manchester Police were called to an address in Clough Avenue, Sale, at about 4.35pm on Saturday.
They forced their way in and the bodies of the 68-year-old man and 65-year-old woman were discovered.
A post-mortem examination revealed both had died from gunshot wounds.
Police said the arrested man remains in police custody for questioning.
Superintendent Wayne Miller said: "Understandably, these deaths have caused shock and upset amongst the local community.
"However, I can reassure them that we do not believe this was a random incident or there is any threat to residents.
"Although an arrest has been made, we are still in the early stages of the investigation and are trying to establish what happened in the lead up to the deaths.
"Patrols have been stepped up in the area to provide reassurance and I would ask anyone who has any concerns about what has happened to speak to their local officer."