Johan Ordonez / AFP - Getty Images, file

Prostitutes come out of a tunnel where they remained hidden during an operation against human trafficking at the "Super Frontera" bar, late on April 21, 2012 in Guatemala City.

More than 42,000 adults and children kept as slaves, forced into prostitution or otherwise trafficked were discovered by authorities around the world in 2011, according to a new report by the U.S. State Department.

However this figure was a tiny fraction of the estimated number of people held in bondage with the International Labor Organization estimating earlier this month that there are about 20.9 million victims of modern slavery, the State Department Trafficking in Persons Report noted.

Under the Trafficking Victims Protection Reauthorization Act of 2003, foreign governments must supply information about trafficking investigations and prosecutions to the State Department in order to be considered by the U.S. as working to eliminate slavery.

The report details the problem of trafficking in countries around the world, including victims' accounts.

"I walk around and carry the physical scars of the torture you put me through. The cigarette burns, the knife carvings, the piercings … how a human being can see humor in the torture, manipulation, and brainwashing of another human being is beyond comprehension. You have given me a life sentence," it quotes a victim of sex trafficking in the U.S. as telling her trafficker at his sentencing.

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Another trafficking survivor in the U.S. named "Tonya" said she "always felt like a criminal."

"I never felt like a victim at all. Victims don't do time in jail, they work on the healing process. I was a criminal because I spent time in jail," she said.

'Like she was our own daughter'
Ken Burkhart, a U.S. Immigration and Customs Enforcement agent, described the liberation of a Latin American sex trafficking victim.

"I told my agents we're going to treat this little girl like she was our own daughter. We're going to hunt this little girl down and get her out of this trailer," he said, according to the report.

After she was found, "I told her we'd been in touch with her sister and I shook her hand and I just gently led her right out the door," he added.

State Department

Graphic showing persons in forced labor in different parts of the world.

The offense of trafficking involves "the recruitment, harboring, transportation, provision, or obtaining of a person for labor or services, through the use of force, fraud, or coercion for the purpose of subjection to involuntary servitude, peonage, debt bondage, or slavery."

It applies where people have been forced into prostitution; victims do not necessarily need to have been physically moved from one location to another.

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In a letter included in the report, Secretary of State Hillary Clinton noted the U.S. would celebrate the 150^th anniversary of Abraham Lincoln's Emancipation Proclamation in the coming months and said that "governments across the globe are united in this struggle."

"Yet, despite the adoption of treaties and laws prohibiting slavery, the evidence nevertheless shows that many men, women, and children continue to live in modern-day slavery through the scourge of trafficking in persons," she added.

Clinton moved by girl's 'pride'
Clinton said earlier this year she had visited a trafficking shelter in Kolkata, India.

"The young women and girls there had suffered terrible abuse. But with their own drive and determination and with the help of some remarkable women and men they were getting their lives back on track," she said.

"I met one girl, about ten years old, who asked if I wanted to see the martial arts she had learned at the shelter. As she performed her routine, I was impressed with the skills she had learned; but more than that, I was moved by the pride in her eyes – her sense of accomplishment and strength," she added.

The Secretary of State said trafficking people deprived people of the "most basic freedom" – being able to determine their own future.

"A century and a half after the promise of freedom was fought and won in the United States, freedom remains elusive for millions," Clinton said. "We know that this struggle will not truly be won until all those who toil in modern slavery, like those girls in Kolkata, are free to realize their God-given potential."

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LONDON -- St. Patrick, patron saint of Ireland, may well have been a tax collector for the Romans who fled to Ireland where he could have traded slaves to pay his way, according to new research by a University of Cambridge academic published on Saturday.

The generally accepted account of the saint's life, albeit based on scant evidence, says Patrick was abducted from western Britain as a teenager and forced into slavery in Ireland for six years during which time he developed a strong Christian faith.

Afterwards, the account continues, he escaped his captors and went back to Britain before eventually returning to Ireland as a missionary.

But Roy Flechner, from the Department of Anglo-Saxon, Norse and Celtic at Cambridge, believes there are reasonable grounds to question the popular version which is based partly on Patrick's own words.

"The problem with this account is that he was telling this story in response to accusations leveled against him that he fled to Ireland for financial gain," Flechner told Reuters in a telephone interview.

"It's an inference that has been made long before in conventional scholarship."

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According to the study, published on Saturday to coincide with St. Patrick's Day, the saint may have wanted to leave Britain in the early 400s to avoid the "onerous" duties of a "Decurion", or Roman official responsible for collecting taxes.

Patrick's father was a Decurion and, when he decided to rid himself of the post by becoming a cleric, his responsibilities would have fallen to his son.

Slaves were his 'liquid assets'
At a time when Roman government in Britain was in decline, collecting and underwriting taxes would have been an unwelcome task, enough to prompt Patrick to emigrate, Flechner said.

"It is likely that at least for a while he (Patrick) held an imperial office. One way or another, I think this would have been the catalyst for him leaving for Ireland."

The academic also questioned Patrick's own account of escaping slavery in Ireland.

"Once you escaped from slavery you lacked any legal status and anyone could imprison you and kill you, and this conflicts with what he said -- that he broke loose, crossed Ireland and then the Irish Sea to get back to Britain," he explained.

"He might not even have been acknowledged as a free man in his native Britain and could have been enslaved again there."

If Patrick had left Britain for Ireland of his own free will, the best way to take his wealth with him would be in the form of slaves, Flechner argued.

Patrick himself said his family owned slaves, which was common for aristocratic families in this period.

"Your property would have been hereditary and in the form of land, but if you had wanted to transport the value of the property, it is more likely you would have traded a more 'liquid asset', in this case slaves.

"In a slightly later period where we do have more sources, slaves had become a very important social institution and quite ubiquitous in Ireland."

Flechner conceded that it was difficult to be sure of any theory about a period of British history covered by so little reliable material.

But he added that his study had the advantage of being "free from the more reverential accounts of St. Patrick that have been handed down in legend through the generations.

"In this case we are seeing Patrick through the eyes of Roman law which offers a new perspective.

"None of this is to say that Patrick was not a bishop or that he did not engage in missionary activity, but his primary motives for moving to Ireland were most likely to escape the poisoned chalice of his inherited position in Roman Britain."

Reuters contributed to this report.

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