A teenager was among four people who died after a small boat capsized in the Channel, it has emerged, as search operations ended on Thursday evening.
Eight unaccompanied children were among 39 people rescued at about 3am on Wednesday, most of them pulled out of the icy waters.
More than 400 people crossed the Channel in small boats on the same day, the Ministry of Defence (MoD) said.
The Kent county council leader, Roger Gough, told a meeting the teenager was among the dead, adding that the tragedy was a “sobering reminder of the human costs of what is an ongoing crisis”.
The Marine Accident Investigation Branch (MAIB) is reviewing evidence of the incident to decide whether an inquiry should be launched.
A government spokesperson said: “The extensive search coordinated by HM Coastguard for people missing from a small boat in the English Channel was concluded at 1700 today. A total of 43 people were recovered from the water, sadly including four fatalities.
“Our thoughts continue to be with those affected by this tragic incident and with the families of those who have lost their lives. We would like to thank everyone involved in the search and rescue operation.”
The RNLI lifeboat charity has praised a fishing boat crew who were first on the scene and “undoubtedly saved countless lives”.
Ben Squire, the owner of Plymouth-based Oceanic Drifter Fishing, said a team onboard one of his scallop boats helped to pull 31 people from the water.
“The skipper called me to tell me he was involved in a serious incident,” he told ITV News West Country.
“They were fishing mid-Channel, halfway between England and France, and a rigid inflatable boat with people onboard, migrants, was crossing and was sinking very, very near to where he was fishing.”
The MoD said 401 people had been detected in eight boats on Wednesday, not including those who had died. The latest figures take the provisional total number to have made the crossing so far this year to 45,223, an analysis of government data shows.
Suella Braverman, the UK home secretary, and her French counterpart, Gérald Darmanin, released a joint statement, sending “our deepest condolences to the loved ones of those involved” and emphasised the two countries’ cooperation in the rescue efforts.
The pair said the incident was “a stark reminder of the urgent need to destroy the business model of people-smugglers” who charge large sums to facilitate the crossing.
Rescuers from the fishing boats said they had been told that people had paid £5,000 for a place on the dinghy, with people coming from Afghanistan, Iraq, Senegal and India.
In November last year, at least 27 people drowned when an overcrowded dinghy sank. Accusations followed that French and British authorities had passed the buck and failed to coordinate a proper rescue – and Wednesday’s efforts suggested a greater coordination between the two countries.
A distress call was first received at 1.53am UK time on Wednesday by a charity in northern France, with a man calling for the alarm to be raised to save his family who were in the icy waters. “Please help me, bro, please, please, please. We are in the water and we have a family,” he said.
The alarm was raised with the UK and French authorities at 1.59am. The major rescue operation began at 2.16am and involved the Royal Navy, French navy, coastguard, RNLI lifeboats, ambulance service and police.
None of the survivors were in hospital and their claims will be processed by the UK immigration authorities in the normal way once any further police and medical checks are complete.
Braverman’s plans to send asylum seekers to Rwanda, which the prime minister, Rishi Sunak, has backed, could face further setbacks on Monday when the high court is due to rule on the policy.
Two judicial reviews were brought against the scheme, under which people seeking refuge are sent to the central African country before their claims are processed.
Priti Patel, then home secretary, announced the deal in April. It has so far cost £140m, already spent by the Rwandan government. No flights have yet taken off.
More than 40,000 people have crossed the Channel in small boats this year to try to reach the UK, typically paying several hundred or a few thousand pounds for the dangerous crossing, which can take five hours or more.
Many came from conflict-ridden countries such as Syria, Afghanistan or Sudan and the grant rate of asylum applications is more than 90% in initial cases. Their numbers have risen as a result of growing numbers coming from Albania, and earlier this week Sunak said he would seek to speed up the return of people to the Balkan state, because the country was not involved in a war.
