A police officer was repeatedly punched in the head in a daylight attack that ended only when a member of the public stepped in.
The officer was patrolling the Orewa CBD about around 12.40pm when he stopped to speak to a man who was drinking whiskey from a bottle in an area with a liquor ban, police said.
When the man began swearing, in front of families with young children, the officer tried to arrest him.
The man ran off and the officer followed but a there was a struggle as the officer tried to restrain him and one of the man's associates joined in, punching the officer repeatedly in the head.
A member of the public who was driving past stopped his car and attempted to pull the attacker off the officer.
Backup arrived and the man ran away. He was arrested at a nearby property shortly afterwards.
The officer suffered bumps and bruises to his head, elbows, knees and neck.
"Our officers work really hard to make sure the community is safe and feels safe and this sort of cowardly rubbish is totally unacceptable," said Rodney area commander Inspector Mark Fergus.
"What is heartening though is the fact that a member of the public stopped to lend a hand. We don't actually know who that person was at this stage and we'd really like to say thanks very much, so please get in touch if it was you," he said.
Two men aged 41 and 34 have been charged with assaulting a police officer. The younger man was also charged with escaping custody.
They will appear in North Shore District Court on December 10.
Anyone who may have witnessed the incident was asked to call Rodney police on 0(9) 426 4555.