The Italian government said on Monday that a rise of migrant boats seeking to cross the central Mediterranean was being driven by the Russian mercenary group Wagner as part of Moscow’s effort to retaliate against nations supporting Ukraine.

In a statement, Defense Minister Guido Crosetto said: “I think it is now safe to say that the exponential growth in the migratory phenomenon leaving African shores is also, to a not insignificant extent, part of a clear strategy of hybrid warfare that the Wagner division is implementing, using its considerable weight in some African countries.

Some 20,000 people have reached Italy so far this year, compared to 6,100 in the same period of 2022, interior ministry figures show, and the migration issue is piling pressure on the rightist government.

In an expletive-laden voice message posted on his Telegram channel, Wagner chief Yevgeny Prigozhin responded: “We have no idea what’s happening with the migrant crisis, we don’t concern ourselves with it.”

He then used a series of obscenities to describe Crosetto and to urge him to pay attention to his own country.

Wagner forces have been accused of operating in several African countries including Libya, Mali, and Central African Republic. They have also spearheaded Russia’s attempt to take the Ukrainian city of Bakhmut.

Crosetto, a senior figure in Prime Minister Giorgia Meloni’s right-wing Brothers of Italy party, called on the NATO allies to help Italy face the rise in migrant arrivals.

“The Atlantic Alliance becomes stronger if the problems arising from collective choices are also shared, but it runs the risk of cracking if the countries most exposed to retaliation of various kinds are left alone,” he said.

Similar remarks also came from Foreign Minister Antonio Tajani, who during a visit to Israel told ANSA news agency that it was worrying many migrants came from areas “controlled by the Wagner group”.

Meloni, who takes a hard line against illegal immigration, came under fire after a shipwreck last month near the southern region of Calabria in which at least 79 died, on allegations the emergency response was slow.

On Sunday, a boat capsized after departing from Libya and charity Alarm Phone blamed Italy for not sending its coastguard despite being repeatedly alerted on Saturday that the boat was in trouble.