Peter Eric Greener, 77, and Sheila Jackson, 83, died following the incident at their home in St Helens, Merseyside, last week.
A 31-year-old man has been arrested on suspicion of murder after the deaths of an elderly couple following a fire at their home in St Helens, Merseyside Police said.
Peter Eric Greener, 77, known as Eric, died on July 16 and his partner Sheila Jackson, 83, died on July 17 following the fire at their home on South John Street in the early hours of Tuesday.
Merseyside Police said an accelerant was used to start the blaze.
The man from St Helens was arrested in the early hours of Sunday on suspicion of murder and remains in custody for questioning.
Detective Superintendent Rachel Wilson, senior investigating officer, said: “Although an arrest has been made, I would like to take this opportunity to remind people to pass on information directly to police or anonymously via Crimestoppers, and not to comment or post in any way which jeopardises this ongoing work.
“Extensive inquiries continue, and to that end we are still appealing for anyone with information to come forward, particularly if you live in the area of South John Street and recall seeing or hearing anything suspicious at around the time of the incident. Please do not assume what you know has already been reported to us, as we can quickly make that assessment.”
On Friday, pictures of the couple, including one showing Mr Greener with his arm around Ms Jackson, were released by their families through police.
Detective Chief Inspector Steve McGrath said last week it was “sickening” and “a truly shocking incident” and everyone in Merseyside would be “utterly appalled” at what had happened.
Anyone with information should contact Merseyside Police by calling 101, quoting incident reference 25000580909, or through social media on X @MerPolCC or on Facebook at Merseyside Police Contact Centre.
Information can also be given through Crimestoppers anonymously on 0800 555 111.
