A tragic start to the New Year for one family, after the death of a man who had been found badly injured in Kaitaia.

The 35 year old died this afternoon in Whangarei Hospital, prompting police to launch a homicide investigation.

Emergency services treated the man on the roadside in Bonnett Road at around 11 last night, where a group were attending a function.

He was taken by ambulance to Kaitaia Hospital, transferred to Whangarei Hospital's Intensive Care Unit and placed on life support.

Detective Inspector Kevin Burke said it appears there had been an unprovoked attack.

Police want to hear from anyone who attended the function.

A scene examination will be completed today and a post mortem examination will be carried out to determine the cause of death.