Protesters clashing with police while blockading a defence industry conference in Wellington have been carried from the venue.

Shouting "army of the rich, enemy of the poor", the group had set out to make life uncomfortable for those attending what protesters have labelled a weapons expo.

At least three people appear to have been carried and escorted away from the scene by police, one in handcuffs.

Nine people have been arrested for obstructing a roadway, said Inspector Neil Banks.

"Uncle Scam" Shane Hayes Anti arms protester. Photo / Ruby Spink

Eight were arrested for obstructing a public road, and one for disorderly behaviour. Police say "a number" were released on bail to appear in court at a later date.

Banks said the protesters needed to keep the safety of themselves and others in mind.

"Police must balance the lawful right to protest against the public's right to go about their daily business without being disrupted by protest action.

"We are disappointed that a number of protesters behaved in a way that created safety issues, disrupted traffic, and caused delays that inconvenienced the wider public.

"I would like to acknowledge the patience shown by our staff, who conducted themselves with professionalism and acted appropriately based on the situation that was presented to them.

"We are aware of allegations in the media about police conduct, and would remind anyone with concerns that there are several avenues available to them if they wish to make a complaint."

At the protest, officers told the group "we don't want anyone hurt".

At the time, protesters were pushing up against police and forcing them onto the road outside Westpac Stadium, where the New Zealand Defence Industry Association forum is being held.

The forum includes discussions on emerging technologies and cybersecurity. The association denies it is an expo, saying it is a chance for business to engage with the defence forces.

Protesters starting gathering about 7am. Among them is new Green MP Chloe Swarbrick, who told TVNZ Kiwis needed to stand up for change.

"I think it's really crucial we do things like protest, that we do stand up, that we do have those difficult and uncomfortable conversations because otherwise nothing is ever going to change," she said.

The protesters are connected with Peace Action Wellington.

Delegates let into conference Wellington protest. Photo / Ruby Spink
Delegates let into conference Wellington protest. Photo / Ruby Spink

"It's important to act and to target the drivers of war, those who make billions of dollars from killing people," protest spokeswoman Jessie Dennis said.

"[Today] is our opportunity to shut down their business, to mess with their profit and to ultimately make the world a better and safer place."

She said the group was there to stay.

"We think it's totally unethical that New Zealand plays host to a weapons expo, and we're not leaving until the weapons dealers do.

"We're standing strong. Groups from all over New Zealand have come together for this blockade, from Auckland Peace Action, Peace Action Hamilton, People Against Prisons Aotearoa, Palestine Solidarity Network, Whanganui Positive Activists, It's Our Future Manawatu, Oil Free Wellington, Unions Wellington, Pacific Panthers, Quakers and Catholic Workers."

Motorists are being asked to avoid the roads around Westpac Stadium as protesters spill onto the street.

Police said Waterloo Quay is being intermittently blocked in both directions by the protest.

They say motorists should take alternative routes if possible.

It's the third year in a row protesters have targeted the week-long conference, using it as a chance to rally against war, violence and weapons.

Anti arms protesters at Westpac Stadium. Photo / Ruby Spink
Anti arms protesters at Westpac Stadium. Photo / Ruby Spink

Two years ago, more than two dozen were arrested after 75 people, one dressed as the grim reaper and others holding masks of former prime minister John Key, locked arms to stop delegates entering the forum. This year's costumes included a clown.

Global weapons manufacturer Lockheed Martin sponsored last year's forum, which was attended by about 700 defence industry and government representatives.

Forum organisers said at the time the defence sector generated $60 million for the New Zealand economy and employed 2500 people.