An armed gang of men attacked two cyclists – stabbing one of them – on a bike path in Renfrewshire.
The assault happened near Milliken Road, Kilbarchan, shortly after 10.20pm on Wednesday.
A group of up to eight men approached two others who were cycling on the path before launching an unprovoked attack.
A 37-year-old man suffered a number of serious injuries, including stab wounds. He was taken to the Royal Alexandra Hospital in Paisley for treatment.
A 29-year-old man also suffered facial injuries was also taken to the same hospital for treatment and has since been released.
Detective inspector Ian Ross said: “This attack appears to have been unprovoked and we are carrying out extensive enquiries to identify those responsible.
“Anyone who was in the area on Wednesday evening and may have seen or heard a disturbance or who has any other information is urged to come forward.
“Anyone who can help our enquiries can call 101, quoting incident 4285 of 27 May, or call Crimestoppers on 0800 555 111”.