A 74-year-old man has suffered "horrendous, life-changing injuries" after being shot with a crossbow.
It happened outside his home in a remote area near South Stack Road in Holyhead, Anglesey, in the early hours.
North Wales Police said the victim was trying to fix a satellite dish on his home when he was hit with the bolt.
He managed to get back inside and raised the alarm at about 00:30 BST on Friday. He remains in a critical condition at Ysbyty Gwynedd in Bangor.
Hospital staff alerted police at 02:45 after a medical examination showed the man had suffered injuries consistent with being shot with a crossbow, police said.
Det Ch Insp Brian Kearney said: "The elderly member of our community has received horrendous, life-changing injuries as a result of this incident, the motive of which remains totally unknown.
"We are in the early stages of our investigation and are working hard to establish the circumstances behind this incident.
"A number of inquiries are under way involving detectives from CID, the local policing teams and crime scene investigation.
"North-west Wales and Anglesey remains one of the safest parts of the UK. Incidents of this nature are extremely rare and we and determined to find out who has done this."
Holyhead town councillor Jennifer Saboor said: "This is a horrendous incident with a 74-year-old man fighting for his life in hospital. It's frightening that this can happen and our immediate thoughts are for the gentleman to pull through."
Police are trying to find anyone who saw anything suspicious near the junction of Porthdafarch Road and Plas Road between 18:00 on Thursday and 04:00 on Friday.