The leader of New Caledonia's CSTNC union, Sylvain Nea, has been arrested as its strike is in its ninth week.
Mr Nea is being questioned in relation to several issues, including the alleged misappropriation of an estimated 120,000 US dollars belonging to the social committee of the SLN nickel company.
He is also being questioned over public statements which police say amount to public insults.
Police also seek to determine his responsibility in relation to numerous roadblocks erected as part of the CSTNC general strike, illegal meetings and breach of freedom of work.
The SLN company has incurred tens of million sof dollars in losses as a result of the CSTNC action.