Kim Jong Il, the eccentric leader of North Korea since 1994, has died at the age of 69.

North Korea’s state-run KCNA news agency reported that after “great mental and physical strain,” he passed away of a heart attack at 8:30 a.m. Saturday while on a train during a “field guidance tour.”

The diminutive Kim had been in power since 1994.  Under his leadership, North Korea’s nuclear program and the many international attempts to stymy its nuclear weaponry potential put him at odds with more than a few other nations, including neighboring South Korea — which declared an “emergency alert” when news of his death broke — as well as the United States.

Kim’s governing style also made him a target of human rights groups. He lived lavishly but at the same time requested international aid after extensive famines that contributed to the deaths of hundreds of thousands of his people.

A statement from the White House said US officials are “closely monitoring reports” of Kim’s death and are “in close touch with our allies in South Korea and Japan,” adding, “We remain committed to stability on the Korean peninsula, and to the freedom and security of our allies.”

Kim’s funeral will be held December 28 with a national mourning period lasting until December 29. His son, Kim Jong Un, is expected to assume his position of power.

[CNN]