At least 12 migrants died off the northern French coast on Tuesday trying to cross the Channel to England in the deadliest such disaster this year, the French government said, as a major rescue operation was underway.
Announcing the death toll on X, French Interior Minister Gerald Darmanin also said that two migrants were still missing.
Several were wounded after their boat carrying dozens ran into trouble off Wimereux, a town some five kilometres (three miles) from Boulogne-sur-Mer on the French coast.
Darmanin said he was travelling to the area of the disaster to meet with officials. "All government services are mobilised to find the missing people and treat the injured," he said.
Emergency services were out in force and supplying urgent medical assistance, French maritime authorities said.
Many of the migrants were in a critical state. A source close to the investigation said the dead included three minors.
Crew on a French government-operated ship, the Minck, were the first to become aware of the emergency and to respond, naval officer Etienne Baggio told AFP.
French navy helicopters, fishing boats and military vessels are being mobilised for the operation, which is still ongoing, he said.
It is the deadliest such disaster this year which has already seen 25 people die in migrant crossings, up from the 2023 death toll of 12.
The French and British governments have for years sought to stop the flow of migrants, who pay smugglers thousands of euros per head for the passage to England from France aboard small boats.
British Prime Minister Keir Starmer and France's President Emmanuel Macron had earlier this summer pledged to strengthen "cooperation" in handling the surge in undocumented migrant numbers.
But on Monday alone, 351 migrants crossed in small boats, with 21,615 making the journey this year, according to UK government statistics.
The crossing often proves perilous, and in November 2021, 27 migrants died when their boat capsized in the deadliest single such disaster to date.
French authorities seek to stop migrants taking to the water but do not intervene once they are afloat except for rescue purposes, citing safety concerns.
Starmer has cancelled a plan by Britain's former Conservative government to send irregular migrants to a holding camp in Rwanda.
The British government is now planning "a major surge" in returns of irregular migrants to countries including Iraq, an official said Thursday, as it tries to clear an asylum backlog.
Meanwhile, both governments are seeking to break the business models of the people-smuggling gangs who organise the crossings and are paid thousands of euros by each migrant for the risky trip.
