Four young Eritreans are fighting for their lives with gunshot wounds after the most violent clashes ever between migrants at the French port city of Calais.
An Afghan man, suspected of opening fire as meals were being handed out on Thursday, is being sought by police.
Local aid groups helping migrants have been told the government will soon take control of food distribution. The demand is high.
"Calais at the moment, (it's) around 700 people and up to 100 under the age of 18, including children as young as 10 years old, sleeping in the woods, sleeping outside. The living conditions are inhumane," said Joshua Hallam, field manager with migrant aid group "Auberge des migrants".
"Some tents or pieces of plastic or sleeping bags are confiscated from them by the police on average 3 times a week."
The French government will also send more police to Calais where despite the dismantling of a sprawling camp in late 2016, asylum seekers and economic migrants continue to gather hoping to reach the UK. They also continue to fall prey to smugglers undaunted by a long-running security operation.
Eritreans and Afghans fought running battles in broad daylight on Thursday, some armed with rods and metal poles, television pictures showed. In all, 22 people were injured.
Calais Mayor Natacha Bouchart said her town was confronted by all-out gang warfare.
"There will be people here at their wits' ends faced with this increasingly violent presence among a certain number of migrants, who it is plain to see are organised in gangs," Interior Minister Gerard Collomb told reporters after spending the night in Calais.
"We know there are gang leaders ... and it is these networks we must dismantle," Collomb said.