Hawaii island police are investigating a pedestrian fatality that occurred Sunday night in the northbound section of Highway 11 in Volcano.

Police responded to a call at 9:45 p.m. on Sunday fronting Glenwood Park and found Patrick Murphy, 34, of Mountain View performing CPR on an unresponsive man in a grassy area about 20 feet from the highway.

The 40-year-old man was transported to Hilo Medical Center, where he was pronounced dead about an hour later. Police said his identity will not be disclosed pending positive identification and notification of next of kin. An autopsy has been ordered.

Police said Murphy was traveling north on Highway 11 in a 2003 Toyota Tacoma truck when he struck the man in the northbound shoulder lane. He initially thought he had struck a pig and continued on to an acquaintance’s residence before returning to the scene.

He called 911 when he realized he had struck the man on the ground and started CPR.

Police arrested Murphy for first-degree negligent homicide, operating a vehicle under the influence of an intoxicant, accidents involving death or serious bodily injury, and duty to give information or render aid.

Murphy is being held at the East Hawaii Detention Facility as the investigation continues.

Police ask any witnesses or anyone with information about this incident to contact Officer Jerome Duarte at 808-961-2339 or Jerome.Duarte@HawaiiCounty.gov. Tipsters who prefer to remain anonymous may call Crime Stoppers at 808-961-8300.

Police said this was the 8th traffic-related fatality this year compared to 16 at the same time last year.