A man suffered serious injuries when he was stabbed in the neck in Preston.
It happened at an address on Farringdon Crescent, Farringdon Park, at around 12.30pm on Monday.
Ambulance crews were called to the property and the 34-year-old man, named locally as Ronnie Kirkham, was taken to Royal Preston Hospital where he was in a stable condition.
Paramedics alerted police to the address and a 52-year-old man, believed to be the victim's step-father, was arrested on suspicion of attempted murder at the scene.
He is in custody being questioned by detectives.
A spokesman for Lancashire police said: "A man was stabbed during a domestic dispute.
"The victim was quite seriously injured."
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