Six fire crews were called to the blaze which broke out in Gorse Avenue, off Ingleway, shortly after 9am.
An air ambulance was also called to the scene and landed on the playing fields at nearby North Drive Park.
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Paramedics attended to a man in his 50s but he was sadly pronounced dead at the scene.
Fire crews reported that a casualty was rescued, but it’s not clear at this stage whether this was the man who sadly died or a second casualty.
The Gazette has asked Lancashire Police for further details about the number of casualties.
Lancashire Police said a joint investigation into the cause of the fatal fire is taking place alongside the fire service.
Anyone with information is asked to call police on 101, quoting log 0450 of July 30, 2022.
Last night, a spokesman for the force said: "We were called to Gorse Avenue, Thornton Cleveleys, at 9.13am on Saturday (July 30) to reports of a fire at a house.
"A man in his 50s was treated at the scene. Despite the best efforts of the emergency services, he was sadly pronounced deceased at the property.
"His family have been informed and our thoughts are with them at this difficult time.
"A joint investigation will now be carried out by police and the fire service."
Fire service statement
A fire service spokesman added: “Six fire engines from Fleetwood, Bispham, Blackpool, South Shore and St Annes, and an aerial ladder platform from Preston attended a fire involving two houses on Gorse Avenue in Thornton Cleveleys.
"Firefighters used two jets and one hose reel to bring the fire under control.
"One casualty was rescued from one of the properties.
"Two fire engines and the aerial ladder platform remain at the incident damping down any remaining hotspots.
“A joint investigation with Lancashire Police is underway.”
North West Ambulance Service were approached for comment.