NOUMEA, France (AFP) — French forces smashed through dozens of barricades in a bid to retake the main road to New Caledonia’s airport and a top official said Sunday that Paris would reclaim all of the Pacific territory from independence militants “whatever the cost”.

After six nights of violence that have left six dead and hundreds injured, French government high commissioner Louis Le Franc warned in a televised address that new raids on independence strongholds would be staged.

“Republican order will be re-established whatever the cost,” Le Franc said, adding that if separatists “want to use their arms, they will be risking the worst”.

New Caledonia, with a population of about 270,000, has been convulsed by unrest since Monday, sparked by French plans to impose new rules that would give tens of thousands of non-indigenous residents voting rights.

The French territory off northeastern Australia has long been riven by pro-independence tensions. But this is the worst violence in decades.

Protesters have set vehicles, businesses and public buildings alight and taken control of the main road to La Tontouta International Airport that has been closed to commercial flights.

Authorities say about 230 people have been detained while an estimated 3,200 people are either stuck in New Caledonia or unable to return to the archipelago. Australia and New Zealand have pressed France for clearance to evacuate their citizens.

France says about 1,000 security forces have been sent to the islands.

Some 600 heavily armed police and paramilitaries took part in an operation Sunday to retake the 60-kilometre (40-mile) main road from the capital Noumea to the airport, authorities said.

Forces with armoured vehicles “broke through” around 60 barricades on the road with only minor clashes, Le Franc said.

But heaps of burned cars, wood and scrap metal in place at about 40 barricades would only be removed on Monday and Tuesday. The road has also been badly damaged, the official said.

The highway is needed to restore supply chains as the archipelago faces shortages of items from groceries to blood for transfusions. “We are starting to run short of food,” Le Franc said.

A night-time curfew, state of emergency, ban on TikTok and the reinforcements failed to prevent more unrest overnight Saturday to Sunday.

Unidentified groups set two fires and raided a petrol station, Le Franc’s office said, as well as destroying schools, pharmacy and supermarkets.

The local government said schools would be closed until May 24. But authorities insisted the situation is improving, noting “the night has been calmer”.

Le Franc said security forces would now stage “harassment” raids to reclaim other parts of the Pacific territory held by pro-independence groups.

“Stay hopeful,” he told people who have set up ad-hoc armed groups to defend their neighbourhoods, while warning against violence that could set off a “widespread conflagration”.

“This will all come to an end, believe me,” Le Franc added.

In Wellington, Foreign Minister Winston Peters said the New Zealand military had “completed preparations” for repatriation flights.

Australian tourist Maxwell Winchester and his wife Tiffany were barricaded in a resort on the airport road for days after they were supposed to leave Noumea.

“They basically burned up every exit on the motorway and all the roads that you could use to get anywhere,” he told AFP.

“We’re just about to run out of food,” he said, adding, “Every night we had to sleep with one eye open… worried that they were coming in to loot us.”

“This morning at an exit near here, the gendarmerie was coming through and there was a shootout,” Winchester said.

New Caledonia has been a French territory since the mid-1800s.

Almost two centuries on, its politics remain dominated by debate about whether the islands should be part of France, autonomous or independent — with opinions split roughly along ethnic lines.

Indigenous Kanaks make up about 39 per cent of the population but tend to be poorer and have fewer years of schooling than European Caledonians. Kanak groups say the latest voting regulations would dilute the Kanak vote.

The presidents of four other French overseas territories — La Reunion in the Indian Ocean, Guadeloupe and Martinique in the Caribbean and Guyane in South America — on Sunday called for the withdrawal of the voting reform in an open letter.

“Only a political response can halt the rising violence and prevent civil war,” they warned, saying they “call on the government to withdraw the constitutional reform bill aiming to change the electoral roll… as the precursor to a peaceful dialogue”.

French officials have accused a separatist group known as CCAT of being behind the violence and placed at least 10 of its activists under house arrest.

CCAT on Friday called for “a time of calm to break the spiral of violence”.