North Korean state-run media reported Monday that Kim Jing-il died on Saturday around 8:30 a.m. while on a train. Korean Central Television said he passed away under "great mental and physical strain."

The North’s state-run Korean Central News Agency said the 69-year-old Kim died of an acute myocardial infarction that triggered a heart attack, and he couldn't be saved despite all possible emergency medical treatment. The KCNA said an autopsy was performed Sunday to confirm the cause of death.

A 232-member funeral committee formed for Kim issued a statement saying a service will be held for the North Korean leader on December 28th. The committee said his body is lying in state at the Gumsusan Memorial Palace in Pyongyang. It added North Korea has announced an official period of mourning to last through the 29th and will not be accepting any foreign dignitaries at this time.

It is believed Kim suffered a stroke in August 2008, but he appeared healthier in videos and photos from recent trips to China and Russia and other trips he made throughout North Korea.

He had brushed away speculations of ill health by taking the night train twice when he visited northeastern China in August 2010. When he revisited the country in May of this year, he moved six-thousand kilometers by train in a week including a 30-hour nonstop train ride from Changchun in Jilin Province to Yangzhou in Jiangsu Province.

Three months later, during his visit to Russia in August, he had regained his weight and his abdomen protruded to the point that his Mao suit looked small on him. He could also use his paralyzed left hand to a degree but was also seen dragging his left foot.

Kim Jong-il ruled the North as Chairman of the National Defense Commission for 13 years from 1998. He was named the official successor of his father and founder of North Korea Kim Il-sung in 1974. Kim Il-sung died in 1994.