NORTH-SOUTH KOREA BORDER -- Thousands of North Korean women fleeing their brutal homeland are ending up as sex slaves in China.
Lured by the promise of food, money and a better life, human smugglers are tricking hundreds of women each year into a life of misery.
"They try to escape from their captors but they get caught," Kang Su Jin told CBN News. "The women are beaten over and over again. Often they get locked up in a room for days."
Since 2006, Su Jin has interviewed dozens of women who escaped from North Korea only to find themselves caught in a web of human trafficking.
Most of the exchanges happen where northern China meets the border of North Korea.
"These women are starving in North Korea so they escape to China in search of food," Kang explained.
"Once they get to China, they are in a new place, they don't know the language, they have no friends and they don't know the environment," Kang said. "That's when the smugglers get a hold of them."
Kang has hours of tape to prove these unthinkable trades. In one video, she interviews a 20-year-old North Korean defector.
"I knew nothing about sexual intercourse. They told me I had to sleep with this guy. I screamed I didn't want to," the young woman told Kang.
"They didn't allow me to go out," she continues. "When I go out, they accompany me, somebody to watch me. It was almost like a prison."
Kang said young female North Koreans have become a commodity for countries like China.
"A North Korean broker handed me over to Chinese brokers," another victim said. "We just followed the brokers. We were treated like products."
China's centuries-old preference for boys, coupled with millions of aborted female fetuses, has resulted in a huge gender imbalance. In one area of Northeast China, the male to female ratio is estimated to be 14 to 1.
In other parts of China there are villages that have no women, driving demand for North Korean "bride slaves."
"She said, 'The guy who bought you asked us to pay 8,000 Yuan, but I bought you at 7,000 Yuan ($1,400). Don't even think of running away.' I was horrified to find that I was sold," one woman recalled.
Trapped in Marriage
The United Nations reports nearly two-thirds of the thousands of North Korean refugees hiding in China are women. About 80 percent of them are trafficked into marriages.
Under international law, women escaping North Korea are considered refugees, but China regularly deports them. So these women face constant threats of arrest and deportation at the hands of their traffickers.
"At the time in May, another investigation of defectors started," another victim recalled. "Many people were arrested and sent back to North Korea. So we took refuge in the woods in a tent."
Kang knows what it's like to be caught in this web of misery. She's from Pyongyang, North Korea, and in 2002 she made a run for China.
"I had a forced marriage in China. I managed to escape from that but got caught by authorities and was sent back to North Korea where I was tortured by prison guards," Kang told CBN News.
"With the help of some contacts I escaped the prison camp and made it here to South Korea via Thailand," she said.
Six years ago she started the Coalition for North Korean Women's Rights to help other North Korean survivors of trafficking.
"I wanted to help these women who have no voice, no one to speak out on their behalf," Kang said.
But many North Korean defectors find it very challenging adjusting to their life in their new settings.
The South Korean government has devoted significant resources to helping them make the adjustment by providing housing, medical services, and education.
Meanwhile, Kang's group focuses on building skill sets.
"Part of the coalition's goal is to provide these women with a steady source of income," Kang said.
"The women begin in this room doing small sewing projects," she said. "Once they've mastered the skill, they move to the next room and work on bigger projects. This is our way of to help them rebuild their lives."
And more defectors are coming. In the last 10 years, 23,000 North Korean refugees reached South Korea. Seven out of 10 are women.
Since the death of dictator Kim Jong Il, the North has stepped up patrols along its border with China. Soldiers have orders to shoot anyone trying to sneak into or out of North Korea.
--Originally aired Wednesday, February 15, 2012.