The attack, which took place before horrified onlookers, is the third in Nouméa in as many weeks.
An Australian tourist has been killed by a shark in front of horrified onlookers in the French Pacific territory of New Caledonia.
The 59-year-old was swimming about 150m (500ft) from shore at a popular beach in Nouméa when he was attacked on Sunday, authorities say.
He was bitten several times, suffering major wounds to his leg and arms, and died at the scene.
It is the third shark attack near the Chateau-Royal beach in three weeks.
Two people sailing nearby took the man back to the beach, where emergency services tried to revive him.
Many people were in the water at the time and witnessed the attack, local media have reported, prompting a panicked rush back to the shore.
Authorities have closed most beaches in the area, and ordered the capture of sharks in nearby waters.
A 49-year-old swimmer was seriously injured by a shark in the area on 29 January, and a surfer was also attacked a few days later.
New Caledonia, which lies south of Vanuatu, is about 1,200km (750 miles) east of Australia.
Though it is home to only 270,000 people, it ranks 13th in the world for the total number of shark attacks, according to the Florida Museum of Natural History, which has kept a tally across the globe since 1958.