A man was battered on the head as he walked along a town centre street less than 100 yards from a police office.
The 31-year-old suffered a deep gash and was rushed by ambulance to Paisley’s Royal Alexandra Hospital.
He needed a number of stitches to the wound and was detained overnight for observation.
The brutal attack happened as he walked home along Inchinnan Road, Renfrew, in the early hours of Sunday morning.
The victim was only a short distance from the police office when he felt a blow to his head and collapsed.
Moments later, he staggered into the Inchinnan Road police station and asked for help. Blood was streaming down his head.
As officers attended to his injury, colleagues called an ambulance.
Police have stepped up their inquiries and yesterday issued an appeal for witnesses.
Detective Sergeant Gordon McCrae said: “If anyone saw this serious assault in early hours on Sunday, September 25, or has information that help our inquiries ring Paisley Police Office on 0141 532 5900 or Crimestoppers on 0800 555 111.”
Officers are checking CCTV footage in the hope the attack was caught on camera.