Four political activists who took over an empty state house in Porirua as part of an election stunt have been arrested and charged.



The men, supporters of Mana by-election candidate Matt McCarten, took over the Porirua property saying they wanted to fix it up for a homeless couple.



Police arrived to arrest them at Iris Grove, shortly after 6pm last night. They were charged with unlawfully being on a property and released on bail.



The men, aged 29, 20 and two aged 22, will appear in court later this month.



Mr McCarten said bail conditions prevented the men from associating with each other - a problem because they all worked on his campaign.



The independent candidate, who is head of the Unite union, was not arrested. He wasn't present when police turned up. The men were released around 11pm last night.



The stunt was aimed at drawing attention to the plight of people suffering from inadequate housing in Porirua, he said.



"State houses are collapsing. Tenants have to pay for repairs themselves. And the rent is too damn high," he said. "It's time for action."



He plans to hold a barbecue at the house on Saturday.



The activists had installed Carolyn Harvey and her partner Ron, who the activists say were living in a garage. They had gone out just before police arrived.



A police spokeswoman confirmed the arrests and said the bail conditions were standard.



The election, triggered by the resignation of Labour MP Winnie Laban, takes place on November 20.