About 300 people in New Caledonia have been protesting near the Vale nickel plant whose operation has been suspended since last week after it became public that an effluent pipe had broken.
The group outside the plant near Goro is made up of members of the environmentalist organisation, Rheebu Nuu, and six local tribes who have called for a review of the terms for the running of the six-billion US dollar plant.
The Rheebu Nuu leader, Andre Vama, says since 2011 the authorities in the southern province haven't inspected the pipe, which carries effluent through a lagoon in a World Heritage site.
It reportedly broke in at least two places, but the Vale leadership says the incident has had no impact on the environment.
Women demonstrators have called for sanctions against Vale.
In the last decade, Rheebu Nuu resisted the construction of the plant and three years ago, the criminal court sentenced 32 members of Rheebu Nuu to suspended jail terms for their role in clashes with police.