A news article on North Korean sweatshop in China

I just read a news article from South Korea. Unfortunately it is written in Korean, so I cannot post it in entirety. However, I translated some interesting parts:

"There are about 20,000 North Korean workers and 400 in Liaoning and Jillin, China respectively... North Korea is eager to send its workers there...It doesn't matter whether a business is one in which South Koreans invest as long as that fact does not appear on official documents...

"The (Chinese) employers can use North Korean workers in half wages they are supposed to pay Chinese workers for equivalent jobs...

"Since 2010 when the Battleship Cheonan sank, the South Korean government banned South Korean businesses from...newly investing in North Korea...and contacting with North Koreans...It is 'impossible' for South Korean firms (operating within China) to hire North Korean workers...

"In one factory, the Chinese employer pays 1,500 yuans, but those North Korean female workers receive only 150 yuans after the North Korean and Chinese authorities take taxes and some 'common expenses'. The next morning after the first pay day, their North Korean managers already took those expenses from the female workers. In their hometown, the local authority takes some money from their families too one the authority notices their daughters have been sent to China for work. However, the remaining money in their hands are still very large amount in their sense, so job application is very competitive."