Peter Eric Greener, 77, known as Eric, died on Wednesday night, and his partner Sheila Jackson, 83, died on Thursday morning following the fire at their home on South John Street in St Helens in the early hours of Tuesday.

Merseyside Police has said an accelerant was used to start the blaze.

On Friday, pictures of the couple, including one showing Mr Greener with his arm around Ms Jackson, were released by their families through police.

A force spokesman said: “We are still in the early stages of the investigation and part of our initial inquiries will be to establish why the fire was started at their house.

“We are 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.”

Earlier this week, Detective Chief Inspector Steve McGrath said: “This is a truly shocking incident and I’m sure that the community and everyone in Merseyside will be utterly appalled at what has happened.

“It’s difficult to comprehend how someone could deliberately start a fire while two elderly people are inside the home.

“It’s absolutely sickening, and we are determined to find the person or people responsible.”

Anyone with information should contact Merseyside Police by calling 101, quoting incident reference 25000580909, or through social media via X @MerPolCC or on Facebook at Merseyside Police Contact Centre.

Information can be given through Crimestoppers anonymously on 0800 555 111.