Twenty-seven people have died near Calais while trying to cross the Channel, France’s interior minister has said.
Gerald Darmanin, speaking from the northern French town, also said five women and a girl were among the victims.
Two people were saved from the water and four suspected people-smugglers have been arrested, he added.
Mr Darmanin had earlier said 31 people had died, but the number was later revised down.
The deaths occurred after an inflatable dinghy capsized near Calais this afternoon, with fishermen reporting more than a dozen bodies motionless in the sea.
Mr Darmanin described the boat as “very frail” and “like a pool you blow up in your garden”, according to a translation.
One UK patrol boat, one French lifeboat, and three helicopters have been involved in search and rescue efforts, which were continuing this evening.
Prime Minister Boris Johnson chaired a meeting of the UK’s emergency COBRA committee in response and held an urgent phone call with French President Emmanuel Macron.
Mr Johnson said he was “shocked, appalled and deeply saddened” and that human traffickers were “literally getting away with murder”.
It is the worst-ever incident involving migrants in the Channel, according to French maritime authorities.
President Macron said: “Europe… is in mourning tonight.” He promised “everything will be done to find and condemn those responsible” and that “France will not let the Channel become a graveyard”.
Following the leaders’ phone call, a Downing Street spokesperson said they “agreed on the urgency” of stepping up joint efforts to stop smuggling gangs and “underlined the importance of close working with neighbours in Belgium and the Netherlands as well as partners across the continent if we are to tackle the problem effectively before people reach the French coast”.