North Korean leader Kim Jong-un visited a landmark mausoleum in Pyongyang on Thursday on the occasion of the fourth anniversary of the death of his father.
  

Kim, known to be in his early 30s, assumed power shortly after the death of Kim Jong-il, who had long ruled the communist nation, on Dec. 17, 2011.
  

Kim paid respects at the Kumsusan Palace of the Sun at midnight, the Korean Central News Agency (KCNA) reported, describing the anniversary as the North's "greatest memorial day."
  

The mausoleum honors Kim Jong-il and Kim Il-sung, the founding leader of the North and grandfather of Kim Jong-un. The bodies of the two late Kims are kept there, along with big statues of them.
  

"A floral basket in the name of Kim Jong-un was placed before the statues," the KCNA said. "Kim Jong-un, together with the participants, paid high tribute to the statues in humble reverence."

Kim was flanked by Hwang Pyong-so, the North's chief military official on political affairs, and Pak Yong-sik, minister of its armed forces.
  

Other top officials in military uniform were also among his entourage.
  

The North seemed to be commemorating the anniversary in a relatively calm mood.
  

A traditional three-year mourning period for Kim Jong-il ended in 2014.
  

The North's state media reiterated calls for loyalty to the current leader. (Yonhap)