Screen queen Lucy Lawless spent 30 minutes locked in a mock prison cell on Friday as part of a worldwide protest action calling for the immediate release of the 'Arctic 30'.
The 30 men and women detained by Russian authorities last month include two New Zealanders; David Haussmann and Jonathan Beauchamp.
They were part of the crew of Greenpeace icebreaker, the Arctic Sunrise, which was seized at gunpoint by the Russian coastguard.
On Friday, 30 Greenpeace New Zealand volunteers - including Lawless - spent 30 minutes each behind the bars of the mock cell on Queens Wharf, central Auckland.
Nicola Beauchamp, Jonathan's sister, was also among the group.
''Jon and his colleagues took a stand for us,'' she said.
''Now we need to stand up for them.''
Greenpeace NZ executive director Bunny McDiarmid said similar events were being held around the world to mark the ''30 days of injustice'' for the Arctic 30.
The crew of the boat has been charged with piracy following a protest against Arctic oil drilling at a Gazprom oil platform in the Pechora Sea.
McDiarmid also spent 30 minutes in the cell representing the captain of the Arctic Sunrise, Peter Wilcox, who was also the captain of the Rainbow Warrior when it was bombed in Auckland in 1985.
''They knew that an Arctic oil spill would decimate a region of breath-taking beauty and would be almost impossible to clean up,'' she said.
''And they knew that we can't tackle the threat from a warming world if we burn the oil under the Arctic. We are here because peaceful activism is not a crime.
''Those 30 brave men and women are not pirates and this charge represents nothing less than an assault on the very principle of peaceful protest.''
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