The New Caledonian SLN nickel company says it will take disciplinary action against about 65 striking employees for sabotaging its sites and assaulting other staff.
This comes as the strike by the CSTNC union is in its eighth week, causing SLN massive daily losses.
The head of SLN, Pierre Alla, has told local radio that while he doesn't contest the workers' right to industrial action, he won't condone violence and the destruction of installations at the mining sites and the smelter in Noumea.
He also says it is unacceptable that people get verbally and physically assaulted.
Mr Alla says SLN regulations allow the company to either sack or demote employees who have been found to have breached these terms.