Kim Jong-un is believed to have ordered the total elimination of his uncle’s biological relatives.
The terrifying purge reportedly started straight after Jang Sung-Taek’s execution and is to demonstrate the Kim Jong Un's "decisiveness."
The North Korean leader is said to be clamping down on any type of mutiny with a brutal iron fist.
Television moitors displayed at the Yongsan electronic market shows the news of Jang Song-thaek's excution in Seoul
“Multiple” sources in Pyongyang told the Seoul-based Yonhap news agency that the executed relatives include Jang's sister Kye-sun, her husband and ambassador to Cuba, Jon Yong-jin, the ambassador to Malaysia, Jang Yong-chol, who is Jang's nephew, as well as his two sons, the sources said.
Underage sons and daughters and even grandchildren of the abovementioned officials were also reportedly killed.
Yonhap’s source said that some victims put up resistance while being dragged out of their apartments and were shot dead “in front of other people”.
Jang, a once powerful North Korean military general, was executed last month as divisions between him and his nephew Kim widened.
Officials referred to Jang as "worse than a dog" and "human scum" in his announcement of his execution, which he said was for treachery and betrayal.
South Korean President Park Geun-Hye has already said the South fears a wave of purges would follow the execution, as 30-year-old Kim seeks to further cement his leadership.
"North Korea is now engaged in a reign of terror while carrying out a massive purge to consolidate the power of Kim Jong-Un," she told a cabinet meeting.