Kim Jong-un 'preparing to purge aunt' "He is trying to bring in a younger generation of decision-makers and has kicked out the older ones, which is causing a lot of problems in the elite in Pyongyang," Toshimitsu Shigemura, a professor at Tokyo's Waseda University and an authority on North Korean affairs, told The Telegraph. "He has been able to do that in the party and the bureaucracy, but he does not have the power to do that with the military," he said. But replacing Kim Kyong-hui might be taking the cull too far, he added. The daughter of Kim Il-sung, the revered founder of the nation, Kim Kyong-hui has long been considered untouchable by any of the various factions in Pyongyang and her replacement - either as part of the ongoing purge or due to ill-health - could trigger a renewed power struggle. "If she disappeared or died, the regime would be badly shaken," said Professor Shigemura. It might even be difficult for it to survive. Meanwhile, Jang Song-thaek's nephew has arrived back in North Korea from his post as ambassador to Malaysia. Jang Yong-chol, his wife and two 20-something sons were sighted boarding an Air Koryo flight bound for Pyongyang in the Chinese city of Shenyang.