A man sought help from the occupants of a flat following a serious assault which put him in hospital in Renfrewshire, police said.
Officers were called to William Street in Johnstone at 6.45pm on Friday.
A 42-year-old man was found to have been injured and was taken to hospital while a 45-year-old man was arrested.
Detectives are unsure where the assault took place and have appealed to the public for information.
Detective Inspector Gordon Smith said: “We have established the injured man sought help from the occupants of a flat on William Street after he was attacked.
“At this stage the location of the attack is unknown.
“I am therefore appealing to anyone who was in the area around the time to contact us with any information.
“Did you see or hear any disturbance? If you have any information, no matter how insignificant it might seem, please do get in touch with us.”
Witnesses are urged to contact Police Scotland on 101, quoting the reference number 3003 of February 21.
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