As Yeon Namsaeng subsequently carried out a tour of Goguryeo territory, however, rumors began to spread both that Yeon Namsaeng was going to kill his younger brothers Yeon Namgeon and Yeon Namsan, whom he had left in charge at Pyongyang, and that Yeon Namgeon and Yeon Namsan were planning to rebel against Yeon Namsaeng.
Da Yeon Namsaeng efterfølgende foretog en rundtur i Goguryeos område, begyndte imidlertid rygter at sprede om, både at Yeon Namsaeng ville dræbe sine yngre brødre Yeon Namgeon og Yeon Namsan, som han havde efterladt ansvarlige for Pyongyang, og at Yeon Namgeon og Yeon Namsan planlagde at gøre oprør mod Yeon Namsaeng.