At least five migrants have been shot in the French port city of Calais, after a mass brawl between Afghans and Eritreans.
Four Eritrean youths aged 16-18 are in a critical condition and have been rushed to a local hospital for surgery, AFP news agency reports.
A fifth man was taken to nearby Lille due to the severity of his injuries.
At least 13 more people were wounded due to "blows from iron bars", the local prosecutor's office said.
French Interior Minister Gérard Collomb visited Calais overnight and said the clashes had been exceptionally serious. One of the most seriously wounded was said to have been hit by a bullet in the back of the neck.
"There's been an escalation of violence that has become unbearable for both the people of Calais and the migrants," the minister said.
The initial fight, which lasted almost two hours, broke out on the city's southern outskirts where migrants had been queuing for food handouts. Around 100 Eritreans and some 30 Afghans were caught up in the violence.
It started when an Afghan fired shots, AFP said.
A second melee then erupted at an industrial site around 5km (three miles) away.
"Police intervened to protect the Afghan migrants faced with 150 to 200 Eritrean migrants," the local prefecture said.
French security forces have been sent to the area.
This is the worst violence between migrants in Calais for months, and the use of firearms is a worrying escalation of the tensions, the BBC's Hugh Schofield in Paris reports.
Though the Calais migrant camp known as the Jungle was demolished in 2016, hundreds of migrants are still living rough in the nearby woods, hoping to reach the UK.
Many of those left are young men.
Local charities put the number of such migrants living in Calais at around 800, while the authorities say there are between 550 and 600.