In the midst of this instability, the chief general and Minister of Defense, Hae Gu, took control of the military and killed Munju's brother Buyeo Gonji in 477.
[1] Since he was not fit to oversee the military, the armies continued to be overseen by General Hae Gu, who maintained actual political control.
In 478, Hae Gu found common cause with rebels led by Yeon Sin, based in Daedu Castle.
He then sent Jin Ro, who defeated the rebels with 500 men, whereupon Yeon Sin fled to Goguryeo.
The next year, Samgeun died, succeeded by his uncle Buyeo Gonji's son, Dongseong of Baekje.