Four people, including two children aged five and eight, have died attempting to reach Britain by boat across the Channel, French authorities have confirmed.
One man drowned when the migrant boat sank, and three people died after they were pulled from the water alive with 15 others, said the official from the Nord department. Another person, possibly a child, is still missing.
Some of those rescued had gone into cardiac arrest, and others suffered hypothermia.
The group’s small fishing boat capsized in the Channel at about 9.30am, the official, Hervé Tourmente, told journalists earlier in Loon-Plage, near Dunkirk.
“It seems that one person, who might be an infant, is still missing,” Tourmente said, noting that stormy conditions had made the attempted crossing especially perilous.
Military resources as well as civilian boats were involved in the rescue operation after the vessel was seen to be in difficulty near Dunkirk.
An English yachtsman reportedly raised the alarm, sparking a large search and rescue operation from the French coast, involving six boats and three aircraft, that lasted well into the afternoon.
French patrol boats and a helicopter from the Belgian air force, as well as a fishing boat, were also dispatched. An investigation has been launched by the Dunkirk public prosecutor.
Tourmente said the boat was carrying Iranian migrants including men, women and children. The aim was to “recover as many people as possible”, he said.
The UK home secretary, Priti Patel, said: “I’m truly saddened to learn of the tragic loss of life in French waters this morning. My thoughts and prayers are with their families and loved ones at this time.”
Patel said the UK was in touch with its French counterparts, who were leading on the response, and have offered support.
“This tragic news highlights the dangers that come with crossing the Channel and I will do everything I can to stop callous criminals exploiting vulnerable people,” she added.
Boris Johnson also expressed his sympathy for those who had lost loved ones. The prime minister tweeted: “We have offered the French authorities every support as they investigate this terrible incident.”