A protester who climbed aboard a Shell oil drilling ship has been arrested after leaving the vessel "for personal reasons".
Aucklander Ilai Amir climbed off the ship this afternoon. He was part of the protest that has garnered international attention because of the involvement of actress Lucy Lawless.
''I’m proud of what we’ve achieved here and I will still be with the team in spirit," Amir said in a statement.
Other activists, including Lawless, have vowed to continue their occupation into a third day.
New Plymouth police sergeant Bruce Irvine said a man left the vessel this afternoon. He was arrested and charged with unlawfully boarding a ship.
He will appear in the New Plymouth District Court on Thursday.
The remaining five activists and Lawless remained camped on the top of the ship’s 53 metre drilling tower, after spending a cold night aboard.
Lawless, best known for her role as Xena in the television series Xena: Warrior Princess, was part of a group of activists who illegally boarded the Noble Discoverer, about 7am yesterday.
The team scaled the ship's 53-metre drilling derrick and unfurled banners reading "Stop Shell" and "Save the Arctic".
Greenpeace campaigner Steve Abel this morning said one of the banners had been ripped by the wind, but the team was planning to put up another one today.
The group had "some sleep" overnight in sleeping bags on steel.
"I don't think they would describe it as comfortable," Abel said.
"They are tired, it's cold up there, but they seem to be feeling well. They are in good spirits and remain on the derrick."
He said Lawless and the protesters were prepared and ready to stay on board as long as they could.
The group boarded the ship to stop the Noble Discoverer make the 11,000-kilometre journey to drill three exploratory oil wells in the Chukchi Sea off the coast of Alaska.
"I've got to say that I couldn't bloody believe it when I reached the top of this drill rig," Lawless said by cellphone. "I couldn't believe it. My heart was pounding. It took me half an hour to get my mind back in my body, I guess that the adrenaline was running so hard."
Police boarded the ship yesterday, but left after meetings with the ship's owners and the port. Police would continue to monitor the situation.
"Although the protesters are breaking the law by being aboard the ship, they are in an isolated location on the ship which allows both the port and the ship to operate their normal business," New Plymouth's area commander, Inspector Blair Telford, said.
"Safety remains paramount and we won't needlessly jeopardise the safety of our staff, the crew of the ship or the protesters."
Police made one arrest at Ngamotu Beach in the harbour and issued two other people with trespass notices from port land.
The protest has drawn world-wide media attention because of Lawless. She fielded calls from the BBC, as well as European and United States media.
Her Wikipedia page, which documents her appointment as a climate ambassador with Greenpeace in May 2009, was updated only hours after she boarded the drilling ship to include her activist misdemeanour.
"It is astonishing to be here 'cause I'm not really cut out for this. I'm not an activist per se. I've never done a direct action on anything apart from being part of a protest down Queen St."
Lawless had been invited to take part in the action to gain maximum attention, but said her concerns were genuine.
"Everybody here is a true believer in the importance of heading off runaway climate change right now."
She said a runaway oil spill under Arctic ice would be too horrible to contemplate.
Meanwhile, security at Port Taranaki is under investigation after the Greenpeace boarding.
It's the third time Greenpeace protesters have targeted vessels at the port. In 2009 graffiti was plastered over a ship in protest at Fonterra's involvement in the palm kernel industry and in October police prevented activists boarding seismic survey vessel Polarcus Alima at the port.
The port, which is owned by Taranaki Regional Council, could increasingly come under attack as it becomes more focused on the oil and gas exploration industry.
Port Taranaki security manager Arun Chaudhari said an investigation into how the protesters were able to get aboard the vessel was under way.
Chaudhari said the port continued to operate as normal yesterday with heightened security.
TRC chief executive Basil Chamberlain said he hadn't been briefed on what had happened or how.
"All I would say as owner, the TRC, we are concerned that there has been a breach of security and I'm sure Port Taranaki people are looking very seriously into how that happened to ensure the security and safety at Port Taranaki."
Does David Cunliffe need to resign as Labour leader?Related story: David Cunliffe's leadership on the line