Kim Jong Il

Kim Jong Il, Kim Jong Il, the diminutive North Korean dictator whose provocations and brinkmanship confounded three U.S. presidents and raised tension across northeast Asia, has died. He was 69.

Kim’s death was announced Monday by state television in a “special broadcast” from the North Korean capital, Pyongyang, the Associated Press reported. The state media report said Kim died of a heart ailment on a train because of a “great mental and physical strain” on Saturday during a “high intensity field inspection.” It said an autopsy was done Sunday and “fully confirmed” the diagnosis.

North Korea will hold a national mourning period until Dec. 29. Kim’s funeral will be Dec. 28, it said.

Kim is believed to have suffered a stroke in 2008 but appeared relatively vigorous in photos and video from recent trips to China and Russia and in numerous trips around the country carefully documented by state media.

South Korean media, including the Yonhap news agency, said South Korea put its military on “high alert.” President Lee Myung Bak convened a national security council meeting after the news of Kim’s death.

Yonhap reported that North Korea conducted at least one short-range missile test on Monday, but two South Korean military officials said they couldn’t confirm the report and that any firing would be part of a routine drill.