The North Korean government under Kim Jong-Un is attempting to once again isolate North Korea from the South by imposing harsher penalties of North Koreans attempting to contact people from the other side of the border.

Human Rights Watch revealed that the North Korean government has intensified its efforts in cracking down possible defectors by increasing "government efforts to monitor, track down, and punish unauthorised phone calls."

"After Kim Jong-Un (took power), anyone caught talking to the South is sent to political prison camps," a woman using the pseudonym of Kim Jin-Seok told HRW.

Because of this, people who work underground to bring people to the South or connect South Koreans with relatives in the North are afraid to continue their work even with the promise of monetary compensation.

"I lost most of my contacts in North Korea and in China since 2013. It does not matter how much money you can pay or what contacts you have, many of the people I worked with are in political prison camps ( kwanliso ) in North Korea or going through trials if they are Chinese," a broker told HRW.

Political prison camps in North Korea are infamous for their human rights abuse record, as well as their high death rates as prisoners are forced to work in harsh environments with minimal food intake. HRW says people who previously attempted defection were subjected to reeducation centres where the environment was less harsh than the political prison camps they are being sent to now.

HRW said rations in the political camps are so meager that inmates suffer from "near-starvation", and there is virtually no medical care, as well as a lack of proper housing and clothes.  Regular mistreatment reportedly includes sexual assault and torture by guards, and executions.

The broker said she used to get calls from North Korea at all times of the day and talk for long periods, but now the number of calls she receives has shrunk by approximately 60 per cent since 2012.

Kim also told HRW that cellular networks no longer have signal in the cities, and that the government could have technology that allows them to locate a call even after it is hung up.

"I used to call from my living room, but later I had to go high up in the mountains in the middle of the night and I was scared to talk for more than a minute or two," she revealed.