A police officer was knocked unconscious after attending reports of an unruly man at a block of Whangārei shops.
The incident happened at the Otaika Shops on Otaika Rd around 4pm on Tuesday.
A witness said she had initially contacted police because a man was making a nuisance of himself outside the shops.
Police said two officers responded at around 3.50pm and began speaking with the man.
A some point "without warning" he allegedly assaulted one of the officers, resulting in a facial injury, before running off.
The witness said she did not see the alleged assault, but saw the man running away across the road being chased by staff and customers from the various shops.
It was then the witness saw a police officer on the ground on the footpath outside the Aussie Butcher. "A lot of people ran to him."
She said she went over and the police officer was unconscious and he had a gash on his face.
The man who had run away was located near NorthTec a short time later.
Police said he was in custody and would appear in the Whangārei District Court on Wednesday to face charges yet to be determined.
Police confirmed the officer had been briefly knocked unconscious.
The officer was receiving medical care and was being supported by police staff and his family.