Four people were shot dead and 23 wounded in protests over the price of air fares between the islands of New Caledonia on Saturday.
The trouble occurred on the island of Mare where airports have been under a blockade.
Users of Air Caledonie have blocked airports since 22 July in protest over a new pricing policy by the domestic airline.
A group of residents of the Mare Ghuama district, whose chief Nidoish Naisseline is also the airline chairman, attempted to dislodge protesters occupying the airfield.
Both groups were armed. Four men were shot and 23 others wounded, some critically.
High Commissioner Albert Dupay says several of the wounded were evacuated by helicopter to Gaston Bourret Hospital in Noumea, while others were taken to a clinic on the neighbouring island of Lifou.
Two platoons of police have been sent to restore order.
Air Caledonie said on Friday it was facing bankruptcy due to the protests, which were costing it more than 80,000 euros ($A108,400) per day. This is the peak holiday season on the islands.
The airline was earlier hit by industrial action that ended on 29 July.