AGGRIEVED PARTY: Jakob Christie and David Linton, who says his face was stomped on, outside a flat.

A teenager says his neck was broken by a baton as police shut down a rowdy Wellington party.

Officers were called to a flat in Homebush Rd, Khandallah on Friday night after uninvited guests started fighting outside.

The gatecrashers fled when police arrived, but partygoers say 18 officers entered the house and drove out the remaining 40-odd guests, using batons to force them down a hallway.

Jakob Christie, 19, said his neck was broken when the end of a police baton was jabbed into it. He woke up on Saturday unable to move his head. X-rays showed that one of his vertebrae had been snapped.

He is in a neckbrace and may need surgery to re-attach a broken piece of bone but he is not paralysed. Mr Christie, a student, said he had asked the officer he thought had hit him for his badge number. He repeated his request to the officer in charge at the scene. "They told me to eff off."

At least six people who were at the party have contributed to a complaint to be submitted to the Independent Police Conduct Authority about the officers' behaviour.

Police insist they were simply trying to gain control of the situation.

Josh Kosmala, 23, who was the sober driver for a group of friends, said most guests were sitting in the lounge when police entered, and were not causing trouble. "It was like running a gauntlet," he said. "[Police] were just being totally unreasonable."

Guest David Linton, 20, said he had his face stomped on by police. He said another person was hit in the stomach with a baton as he sat on a couch.

Robert Morrison, 20, who lives at the flat, said he and a few other people had tried to stop police coming inside by holding the door closed. That could have frustrated police but they should have taken a more low-key approach, he said.

"They could have at least said, 'Can I come have a look inside?' They would have seen there wasn't any trouble."

Wellington police area commander Inspector Peter Cowan said he understood officers had arrived to a confused situation and needed to quickly gain control: "People were fighting on the street, bottles were being thrown. What needs to happen immediately is firm and assertive action."

Wellington City Council had been called that evening by neighbours complaining about the noise, he said.

He was aware of the partygoers' allegations and had encouraged them to make a complaint to the conduct authority.

Mr Cowan said he would not tolerate inappropriate police action, if it was shown that officers had breached the law. "If people need to be held to account we will hold them to account."

Eight people arrested in the incident will appear in Wellington District Court on Friday.