A fire razed most of the Grande-Synthe migrant camp near Dunkirk in northern France overnight after fighting among its inhabitants left several people injured, the region's top government official said early on Tuesday.
The camp, set up just over a year ago and equipped with tightly-packed wooden cabins and sanitation, had housed around 1,500 people, many of them Kurds.
Its population has grown recently with a surge of arrivals from Afghanistan.
"The camp has largely been destroyed," Michel Lalande, prefect for France's Nord region, said by telephone, adding that the fire followed a fight between the Afghans and Kurds there.
Grande-Synthe has been home to one of the largest groups of Britain-bound migrants on the French coast since the closure last October of a sprawling shanty town outside the nearby port of Calais.
Last week, some of its inhabitants tried to block the nearby highway with tree trunks and branches in an attempt to stop the traffic and clamber onto the trucks and cars in the hope of reaching Britain.
Sights like these in recent years to some extent drove Britons to vote for a divorce from Europe last summer.
The large influx into Europe of migrants fleeing poverty and war elsewhere is also a hot button issue in France, where the far-right, anti-immigration leader Marine Le Pen is one of the frontrunners in a presidential election now less than two weeks away.
Le Pen on Tuesday repeated that she would close migrant camps and France's borders, also drastically cutting migration should she be elected.
"This chaos has to end," she said in a statement. Opinion polls show Le Pen tied with centrist Emmanuel Macron in the first round on April 23 then losing to him in a run-off of the two top scoring candidates on May 7.
Lalande said five people had been hurt as a result of the blaze.
At least another five were injured after scuffles and a knife fight broke out in the camp earlier in the evening, regional authorities said. Riot police intervened.
One migrant was knocked over by a car on a highway outside the camp and was in a critical condition.
Lalande earlier told journalists that it was unlikely that the camp, set up by medical aid charity Medecins Sans Frontieres, could be rebuilt.
Much of the camp was reduced to rubble. Migrants were taken to makeshift shelters nearby.