North Koreans forced to work abroad to raise cash for the state's nuclear weapons programme are seen toiling in appalling conditions.
Secret footage has revealed the plight of North Koreans who are forced to work abroad in appalling conditions to raise cash for Kim Jong-un's nuclear weapons programme.
More than 150,000 of the country's workers are overseas as part of an apparent network of 'exported forced labour' around the world, according to a probe by human rights groups and journalists.
An investigation taking in China, Russia and Poland shows labourers toiling in 'slave-like' conditions with one revealing how the back breaking work was their 'revolutionary duty'.
A former North Korean deputy ambassador to Britain, has claimed that cash sent from workers helps to bankroll Kim Jong-un's nuclear ambitions.
One North Korean worker, in the far eastern Russian city of Vladivostok, told a journalist: "You're treated like a dog here. You have to eat dirt, you have to give up being a human being."
Meanwhile, up to 800 North Koreans are believed to be working as welders and labourers in shipyards in Poland, according to a BBC Panorama documentary.
A North Korean foreman at one Polish firm said: "When there are deadlines, we work without breaks. Not like the Polish, they work eight hours a day and then go home. We don't, we work as long as we have to."
In one secretly-filmed clip, site authorities appeared to defend the arrangement, insisting: "They get a glimpse of the world. and they get a few zloty or a few dollars, and this probably helps the entire family."
Companies involved in the documentary have denied any wrongdoing while Pyongyang insists its countrymen are working legally.
However, Thae Yong-ho, the former North Korean deputy ambassador to Britain, said cash sent from workers helped Kim Jong-un's military ambitions and funded the family's luxury lifestyle.
"If this money had been used for peaceful economic development, the economy would be in a much better place," he said.
"So where did all that money go? Well, it financed the private luxury of the Kim family, the nuclear programme and the army."
Facing US and international sanctions, North Korea has relied on its overseas labourers as a way to get cash.
Figures vary on how much North Korea earns annually from its workers. A 2015 U.N. report suggested that North Koreans working overseas earned Pyongyang between $1.2 billion and $2.4 billion a year. Other estimates put earnings in the hundreds of millions of dollars.
The major markets for North Korean workers are China and Russia, but the Gulf also hosts thousands.
Despite many living in poverty, North Korea is understood to spend up to a fifth of its annual GDP on the military.