A man died and a woman was seriously injured when the roof of a house collapsed.
The pair were in a bedroom at their home in Knight's Fold, Bradford, when debris fell on top of them.
Emergency services were called just after 05:00 BST to reports of a "structural collapse".
The man, 47, died while the woman, 28, was taken to hospital. Her injuries are not thought to be life-threatening, police said.
A family from a neighbouring property were taken out of their house unharmed.
Det Insp Claudine Binns said work was under way to make the building safe and it had launched an investigation with Bradford council to determine the cause of the collapse.
She said the victim's family would be re-homed, with local authorities "working to support them in any way we can".
Image copyright PA Media Image caption The emergency services received at a call at about 05:06 BST on Sunday morningRoad closures are in place in the area while police officers, firefighters and structural engineers carry out work.
Officers from West Yorkshire Police are preparing a file for the coroner.
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