U.S. intelligence officials are watching signs that North Korea's unpredictable dictator, Kim Jong Il, may be gravely ill.

Kim Jong Il AP PHOTO

Incapacity of the man North Koreans call "Dear Leader" would have serious implications for the international effort to get North Korea to abandon nuclear weapons.

There was no sign of Kim at a parade and celebration Sept. 9 marking the 60th anniversary of North Korea's founding, and the country's state media was silent about his absence. His last reported public appearance was in mid-August.

"There is reason to believe Kim Jong Il has suffered a serious health setback, possibly a stroke," a Western intelligence official said.