Yesterday, Pope Francis declared that sex trafficking is a "crime against humanity" after following a meeting with four women who were forced into prostitution.

Following a private discussion with the women,  the pope spoke to a conference of church leaders and police chiefs from twenty countries, all of who pledged cooperation to fight the problem of trafficking and encourage victims to come forward.

"Human trafficking is an open wound on the body of contemporary society," the pope stated. "I exhort the international community to adopt an even more unanimous and effective strategy against human trafficking, so that in every part of the world, men and women may no longer be used as a means to an end."

During his time as pope, Francis has raised global awareness of sex trafficking and called on country leaders to fight the problem.  Earlier this year, he wrote a letter of support to the National Catholic Bishops' Conference of Brazil  who launched a campaign against trafficking.  He referred to  trafficking as a "scourge" and wrote that "It is impossible to remain indifferent when one learns that there are human beings who are bought and sold like merchandise."

The International Labor Organization revealed that 2.4 million people are trafficked yearly, with traffickers receiving more than $32 billion a year. According to the Polaris project, 50% of those trafficked are children, and 80% are women and children.

According to the Huffington Post, Cardinal Vincent Nichols, archbishop of Westminster, who served as chair for the conference, said a mere 1 percent of those enslaved have been rescued.

"There is an endless supply of stolen bodies among the poor and desperate in the world," Nichols said. "They are not free. They are slaves."

Sir Bernard Hogan-Howe, London's Metropolitan police commissioner, reported that British police have collaborated with church leaders to raise awareness and free victims of trafficking.  Police have successfully prosecuted 300 cases in the past three years.

Hogan-Howe hopes that with the pope's leadership, countries around the world will come together to fight trafficking.

"Different jurisdictions can work across boundaries," Hogan-Howe said. "We are building networks with the Catholic Church and enforcement agencies. We are not going to give in."

The Catholic Church is remains one of the most outspoken groups against human trafficking. The official website for the denomination states that "the Catholic Church's vehement opposition to human trafficking is rooted in principles of Catholic social teaching, central to which is the sacredness and dignity of human life." The Church believes that "Human trafficking is a horrific crime against the basic dignity and rights of the human person. All efforts must be expended to end it."