Speaking outside a hospital in Calais, Darmanin said that five women and a girl were among the dead. Two people were saved and one person is still missing, he said.
French President Emmanuel Macron and UK Prime Minister Boris Johnson expressed their horror at the tragedy and sent their condolences to the families of the victims.
Macron said his country would not allow the English Channel to become a graveyard and urged his European counterparts to increase efforts to prevent future tragedies.
“To the families of the victims, to their loved ones, I want to express my compassion and the unconditional support of France,” the president said in a statement.
“I assure you that everything possible will be done to find and convict those responsible, smuggling networks that exploit misery and anguish, endanger human lives and ultimately decimate families,” he added.
Macron said France had been working with the UK for several months to dismantle smuggling networks.
“Since early 2021, thanks to the mobilization of 600 police and gendarmes, 1,552 smugglers have been arrested on the north coast and 44 smuggling networks have been dismantled,” he said.
“Despite this action, there have been 47,000 attempts to cross into Britain since January 1, with 7,800 migrants saved by our rescue services.”
The country’s sea minister, Annick Girardin, said French, British and Belgian helicopters were searching for the missing.
French Prime Minister Jean Castex described the incident as a “tragedy”. “My thoughts are with the many missing and injured, victims of criminal traffickers who exploit their anguish and misery,” he said in a tweet.
British Prime Minister Boris Johnson said he was “shocked and appalled, and deeply saddened by the loss of life at sea.”
“My thoughts and condolences are, first of all, with the victims and their families, and it is an appalling thing that they have suffered,” Johnson told reporters.
“But I also want to say that this disaster underscores how dangerous it is to cross the English Channel in this way. And it also shows how vital it is that we now step up our efforts to break the business model of the gangsters who are sending people to the sea of this way, and that is why it is so important that we accelerate if possible all the measures contained in our borders … so that we can distinguish between people who come here legally and people who come here illegally. “
He added that the authorities “would leave no stone unturned to the business proposition of human traffickers and gangsters … who are literally getting away with it.”
Johnson said it is time for the UK, France and Europe to “step up” and work together. He was scheduled to chair a meeting of Cobra’s emergency committee in response to the tragedy, his spokesman said.
UK Home Secretary Priti Patel said in a statement that the tragedy “serves as the starkest possible reminder of the dangers of these Channel crossings organized by ruthless criminal gangs.”
He added: “We will continue to intensify all cooperation with France and other European partners to prevent immigrants from embarking on these deadly journeys.”
On Monday, the French Home Office announced that it will send equipment and vehicles worth more than 11 million euros ($ 12.3 million) as part of an agreement with the United Kingdom, “to secure the coastal strip that will be stretches for more than 130 km, from Dunkerque to the Bay of Somme “.
He added that “the police and gendarmes will have additional resources to carry out the mission of combating illegal immigration.”
Last week, 243 people were rescued in the English Channel as they tried to cross into the UK.
More than 25,700 people have crossed the English Channel into the United Kingdom so far this year in small boats, according to data compiled by the British news agency PA Media. This is three times the total for all of 2020, reports PA.
CNN’s Amy Cassidy and Joseph Ataman contributed to this report.