A new report says some 30 million people are enslaved worldwide.
The report says they are trafficked to work as sex slaves, forced into manual labor, are victims of debt bondage, and sometimes born into servitude.
The "Global Slavery Index 2013
" survey by Walk Free, an Australian-based rights group, says almost half of the world's slaves are in India. But the report says it found slavery in 162 countries.
There are "29.6 million people in the world in slavery. And that's important because we need to know how many people are in slavery and where they are in order to address the problem," one of the authors of the report, professor Kevin Bales, tells RFE/RL.
"We are thinking about it like a disease where you must do the medical research to know the size and the causes of the problem before you can mount a good campaign to stop the disease."
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The report says there are some 516,000 people in Russia who could be considered as living in slavery but Bales also notes Russia is both a destination for slaves and a source for them.
"One of the things that we know is that there is human trafficking from other countries into Russia and there is also human trafficking of Russians to other countries," Bales says. "In some ways it seems [that] the larger part of the problem is the trafficking of men in particular from countries like Moldova and from places like Uzbekistan and Kazakhstan into work like construction and agriculture in Russia."
Bales uses the example of Russia to point out something that is true in other countries. "We know that, as in many other countries, the differences that have to do with ethnicity or nationality are exploited and it means that those people who are different, who are not Russian are more likely to be enslaved and exploited," he says.
Concerning Uzbekistan and the infamous forced cotton-picking campaign the government there initiates every year at harvest time, Bales notes: "If you have a situation in which the national government is requiring people to work and there is a penalty if they do not go to work and if they are enforcing those penalties with force and threats, then you are approaching a situation that could be called state slavery. That situation is one that has a lot of people around the world concerned about Uzbekistan."
And Bales says the justifications the Uzbek government uses on its people are nothing new.
"The Uzbek government says, 'This is not slavery, this is service, this is national service.'" he says. "But I would also point out that throughout the history of colonization, of the European control of Africa, for example, they would often force the local populations to work and refer to it as national service."
The report says China is home to 2.9 million slaves and Pakistan has 2.1 million.
It says Moldovans in Ukraine, Russia, the United States, Germany, Belarus, and elsewhere are exploited in the sex industry, construction, agriculture, and domestic work.
With reporting by Reuters and AFP