A huge fire, apparently started deliberately, has reduced the Grande-Synthe migrant camp near the northern French city of Dunkirk to "a heap of ashes", according to officials.

Firefighters said at least 10 people had been injured in the blaze at the camp late on Monday, which was home to some 1,500 people, mostly Iraqi Kurds, living in closely packed wooden huts.

"There is nothing left but a heap of ashes," Michel Lalande, prefect of France's Nord region, said at the scene as firefighters continued to battle the flames which were visible from several kilometres away.

"It will be impossible to put the huts back where they were before."

READ MORE: In Dunkirk refugee camp, a life of muddy uncertainty

The camp was being evacuated and the migrants would be rehoused in emergency accommodation, the prefect said.

Al Jazeera's Natacha Butler, reporting from camp, said some 400-600 refugees were housed in three gymnasiums in the Dunkirk suburb of Grande-Synthe, but others had dispersed.

"We've seen them walking along the road; their future was so uncertain but of course it's going to be even more uncertain now."

Lalande said the blaze had been started after a fight on Monday afternoon between Afghans and Kurds at the camp that had left six injured with knife wounds.

"There must have been fires deliberately set in several different places," said Olivier Caremelle, chief of staff of Grande-Synthe Mayor Damien Careme, an environmentalist who supported the building of the camp last year.

"It is not possible otherwise. It seems that it is related to fights between Iraqis and Afghans."

Plans to dismantle camp

Fights between the refugees continued after midnight, with riot police struggling to contain them and occasionally being pelted with stones, according to an AFP news agency correspondent.

"No one is able to explain how these events could have happened," said Lalande.

The population of the Grande-Synthe camp has swelled since the destruction last October of the squalid "Jungle" camp near Calais, about 40km away.

READ MORE: Refugee crisis - Cautious welcome to Grande-Synthe camp

According to several witnesses, disagreements arose after an increase in the number of Afghans who arrived from the "Jungle" camp.

The Afghans were apparently unhappy at being put up in the communal kitchens while the Kurds slept in chalets.

Their arrival had increased tensions, according to Caremelle.

There have been several violent incidents at the Grande-Synthe camp, with police intervening last month after five men were injured in a fight. Another man was stabbed in November.

French officials had said in mid-March that security forces were planning to start dismantling the camp following clashes at the site.

The camp, built by the humanitarian group MSF (Doctors Without Borders), opened in March 2016 over the objections of the central government.

For more than a decade France's northern coast has been a magnet for refugees and migrants trying to reach Britain, with French authorities repeatedly tearing down camps in the region.

Migrants gather along the northern coast in France seeking to break into trucks heading to Britain or pay people smugglers to help them to get across the Channel.

The issue is a constant source of friction between Britain and France and an embarrassment for the French government, which has been criticised by the UN refugee agency for failing to provide adequate accommodation.