PYONGYANG - The Democratic People's Republic of Korea (DPRK) held Sunday a national memorial service commemorating the 100th day of the death of their leader Kim Jong-il.

Kim Jong-un, the late leader's successor and supreme commander of the Korean People's Army (KPA) and supreme leader of the Workers' Party of Korea (WPK), attended the memorial service at the Kim Il Sung Square.

Premier Chon Yong-rim delivered a speech at the ceremony and praised the late leader, saying "He successfully solved the issue of succession to the leadership to accomplish the revolutionary cause of Juche".

People observe a moment of silence during a memorial service at Pyongyang's Kim Il-sung Square on March 25, 2012. [Photo/Agencies]

Chon encouraged the countrymen to accomplish "the cause of building a thriving socialist nation under the leadership of Kim Jong Un".

At noon local time (0300 GMT), sirens and whistles sounded  across the country with national flags flying at half-mast. Citizens observed three minutes of silence in reverence towards the Kumsusan Palace of the Sun, where Kim Jong-il's body is on display.

Earlier on Sunday morning, Kim Jong-un and some senior party, state and military officials also paid a visit to the Kumsusan Palace of the Sun.

Kim Jong-il died of a heart attack on a train during a "field guidance tour" on December 17, 2011.

Kim Jong-un attends a ceremony to mark the 100th day since the death of his father, the late leader Kim Jong-il, in Pyongyang March 25, 2012. [Photo/Agencies]