An unprovoked attack on a man in central Auckland has police asking for public help.
The attack happened outside the Auckland Central, on the corner of Lorne St and Rutland St at around 8:50am on Wednesday.
The attacker, who is still unknown to police, is believed to have approached the victim from behind and assaulted him with a hammer, before fleeing the scene.
The victim suffered serious head injuries and was taken to Auckland Hospital, where he remains in a stable condition.
Police have released an image taken from CCTV cameras in the area, showing who they believe to be the attacker.
Acting Detective Inspector Glenn Baldwin said it is an alarming assault.
"This was a shocking, unprovoked and cowardly attack on a victim who was unaware and attacked from behind," he said.
"We want to find the dangerous offender who was responsible for this vicious attack and hold them to account."
Police urge anyone with information to contact Auckland City Police on (09) 302 6557.