 The 1st plenum saw the " revolutionary generation " retire from their executive posts , surrendering them to the new generation of Kim Jong @-@ il ; however , they still controlled the highest organs of power : the Presidium and the Politburo . The plenum saw the disappearance of Kim Yong @-@ ju ( Kim Il @-@ sung 's brother , considered his chosen successor before Kim Jong @-@ il ) , Kim Dong @-@ gyu , Ryu Jang @-@ sik and Lee Yong @-@ mu from important party positions . The reason for the purge is unknown , but presumably linked to Kim Il @-@ sung 's time @-@ consuming consolidation of his son 's power base . 
