Pope Francis spoke out against human trafficking Sunday, calling it a modern form of human slavery.

“I appeal especially to the governments, so that the causes of this plague are dealt with decisively and the victims are protected,” the pope told the crowds gathered for his weekly Angelus message in Saint Peter’s Square. “But we can and must cooperate by denouncing the cases of exploitation and slavery of men, women and children.”

Last summer, the pope called on nations to combat the “shameful crime” of human trafficking, while noting that it is often tied to illegal immigration.

Many adults and children are trafficked into slavery for forced labor, sex businesses, organ trafficking, begging rackets, and other criminal activities, Francis said, adding that “even migratory routes are often used by traffickers and exploiters to recruit new victims.”

In 2017, an Italian public prosecutor said that investigators needed to follow the money trail, since huge financial allocations intended for the reception of migrants were attracting mafia interests and abetting human traffickers.

A report released by Frontex, the border control agency of the European Union (EU), suggested that a number of NGOs had been complicit with human traffickers in providing a shuttle service from North Africa to Italy.

NGOs engaged in maritime rescue operations “help criminals achieve their objectives at minimum cost, strengthen their business model by increasing the chances of success,” the report stated.

A particularly egregious example is that of Nigeria, whose local mafias have been responsible for trafficking women into Italy and then forcing them into prostitution.

During the year 2016, more than a fifth of the 172,000 migrants arriving in Italy were from Nigeria, many of whom were lured into making the dangerous journey by a vigorous promotion campaign promising benefits and opportunities. The majority of the Nigerian women who made the voyage found themselves working as prostitutes once they arrived in Italy.

One 24-year-old Nigerian woman named Gloria Erobaga recounted the harrowing experience of forced prostitution on Italian streets, after she had been promised “honest work” by the mafia traffickers who arranged her passage to Italy.

“They would continually check up on us to collect our money and they killed the girls who didn’t pay,” she said. “I know of Nigerian women in Italy who were killed, cut up and thrown into black garbage bags, like trash,” she added.

According to reports in the Italian media at the time, Nigerian traffickers exploited Europe’s migrant crisis “to take girls to Libya and then across the Mediterranean into Italy,” bringing more than 12,000 girls and young women from Nigeria into Italy in just two years.

Of these, four out of five (80 percent) ended up in prostitution. Currently, one out of every two prostitutes in Italy is Nigerian, the report stated.

Italy’s interior minister Matteo Salvini, who made curbing illegal immigration the hallmark of his election campaign, said last month he is “proud” to have put an end to illegal immigration in Italy and to have halted human traffickers who were using immigration routes to deal in human beings.

In a Tweet to his followers, Mr. Salvini said that by combating illegal immigration he was also fighting human trafficking and the drug trade.

Decrying smugglers and human traffickers, Salvini said he had evidence that “with the money they make—around 3,000 euro for every person they put on the boat—they buy arms and drugs. So stopping the trafficking of human beings does not just mean stopping immigration, but it also means blocking weapon and drug trafficking.”

There has also been a significant drop in migrant sea deaths ever since Salvini closed Italy’s ports to NGOs that were transporting would-be migrants across the Mediterranean Sea.

According to a report last month by the Italian daily La Verità, “the Salvini method works,” referring to Mr. Salvini’s tightened border controls. Salvini has insisted that open ports fuel human trafficking and encourage migrants to undertake dangerous sea crossings.

There was no solution under the former Matteo Renzi government, the newspaper noted, since Mr. Renzi tried to punt the ball to the European Union and wrung his hands when the EU did absolutely nothing to resolve the problem.

“The proof is that after years of useless chatter the departures and arrivals have diminished, indeed almost ceased,” the newspaper declared. “And with falling departures and arrivals, the deaths have also declined. Yes, the statistics say that despite alarms raised by NGOs, as the number of refugees who board a vessel is reduced, deaths have also been reduced.”

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