(Updates with detail on cyber attack paragraphs 2-5, protest organiser paragraph 12-13)
Protesters and a thousand French police reinforcements were playing a "game of cat and mouse" in New Caledonia, an independence group said on Wednesday, ahead of the arrival of France's President Emmanuel Macron after the worst riots in 40 years.
Macron is due to land in the French overseas territory in the Pacific on Thursday after government electoral reforms passed a week ago sparked riots that have killed six people. Some leaders fear the change will dilute the vote of indigenous Kanak, who make up 40% of the population.
The New Caledonia government said a large cyber attack launched soon after the announcement of Macron's visit had aimed to make internet services unavailable, with millions of emails sent to one address.
The attack had been stopped and its origin was unknown, an official said in a livestreamed press conference on Wednesday.
"The different emails that were launched came from several countries at the same time. They wanted to clog the New Caledonia cable," the official said.
France's High Commission said Macron would be accompanied by ministers for defence and interior for Thursday's talks, and some 100 members of the GIGN or elite tactical response group were deployed in New Caledonia.
BARRICADES, FIRES More than 1,000 security reinforcements from France were on the ground, some 90 barricades had been cleared from roads, and the night had been calmer despite two fires in Noumea, the high commission said on Wednesday. Some 20 arrests were made on Tuesday, with 280 rioters arrested in the past week.
Jimmy Naouna, from the Front de Liberation Nationale Kanak et Socialiste (FLNKS) of New Caledonia, said the pro-independence political party had called for protesters to remove road blocks, which are restricting movement and supply of food in the capital Noumea, yet they continue to appear overnight.
"The police forces go around clearing these barricades but the youth right after that, they put them up again, so its almost a cat and mouse game. We will see what happens when Macron gets here," he told Reuters in an interview.
FLNKS, the party of the New Caledonia government's president Louis Mapou, want Paris to scrap the electoral reform.
"We are expecting if he travels to Kanaky he will make some strong announcement that he is withdrawing this electoral bill, but if he is just coming here as a provocation that might just turn bad," Naouna said, using the island's indigenous name.
The protester organiser, Field Action Co-ordination Cell (CCAT), called on social media for protesters to display Kanak flags and banners opposing the electoral amendment.
"We don't know what Macron and his team are coming to do but we remain mobilized and confident for Kanaky," it said.
Macron will meet elected officials and local representatives on Thursday for a day of talks focused on politics and on the reconstruction of the island, his aides said.
France annexed New Caledonia in 1853 and gave the colony the status of overseas territory in 1946. New Caledonia is the world's No. 3 nickel miner but the sector is in crisis and one-in-five residents live below the poverty threshold.
The island is more than 16,000 km (10,000 miles) from mainland France, and some 1,500 km (930 miles) east of Australia.
Over a hundred foreign tourists were evacuated on Australian and New Zealand government chartered flights on Tuesday, as New Caledonia's airport remains closed to commercial flights. The U.S. State Department said one U.S. citizen was among those evacuated to Brisbane.
Australia's Minister for the Pacific Pat Conroy said 84 Australians were evacuated, and 200 more Australians who are seeking to leave remain in New Caledonia.
The French government is organising Wednesday's evacuation flights to Australia, he said.
