A 26-year-old man is in a "serious" condition after driving himself about five miles to hospital after being stabbed in the head, arm and torso.
The man, who was reportedly attacked with a machete, made the 20-minute journey from Netherton Way in Bootle, Merseyside, to the Royal Liverpool University Hospital, despite his injuries.
Police said officers were called to the hospital at around 2.25pm and are appealing for information. They have described his injuries as non life-threatening.
A statement from Merseyside Police said: "It is believed unknown offenders assaulted the man in Netherton Way, Bootle. The victim then drove to the hospital. The man is now at the hospital where his condition is described as serious."
A full investigation has been launched. CCTV is being explored and a cordon was set up outside the hospital for forensic examinations to take place.
Anyone with information can call officers on 0151 777 4060 or Crimestoppers, anonymously, on 0800 555111.