Seven Greenpeace activists have been arrested after painting a large slogan on the side of a ship in the Port of Taranaki.
The activists in two inflatable boats painted 'Fonterra Climate Crime' in three-metre high lettering while the ship was being unloaded.
Police arrested the four men and three women when they returned to shore.
Greenpeace says the protest was part of a campaign to stop the import of palm kernel animal feed destined for Fonterra dairy farms.
Climate campaigner Simon Boxer said the ship had come from Indonesia where rain forests are being destroyed by palm plantations.
Police say the group is accused of intentional damage and entering an exclusion zone without permission and were due to be bailed later on Sunday.
Fonterra has not commented other than to describe the incident as another publicity stunt by Greenpeace.
Last month Greenpeace campaigners boarded a cargo ship off Tauranga.