Reporting from Seoul and Beijing — North Korean leader Kim Jong Il paid a surprise visit to China on Thursday with his youngest son, Kim Jong Eun, in an apparent effort to bolster plans to name him as his successor.
The trip, coming when former U.S. President Carter is in Pyongyang, shows that for the struggling North Korean regime, the succession is paramount to all other concerns.
Highlighting the theme of the family dynasty, Kim Jong Il's first stop was Yuwen Middle School in Jilin City, where his father, North Korea's founder Kim Il Sung, studied from 1927 to 1930. His family had fled there to escape the Japanese occupation of Korea.
Kim's train crossed the border into China about midnight Wednesday, two officials told reporters. "We are still trying to grasp his exact destination and the purpose of the visit," one of the officials told South Korea's Yonhap news service.
Both officials requested anonymity because they were not authorized to discuss the matter.
Kim also visited China in May, meeting with Chinese President Hu Jintao.
The Chinese government Thursday had no immediate comment on the visit. Because of security concerns, Kim's rare trips outside North Korea to the ally nation are publicly confirmed only after they end.
Yonhap quoted an official speculating that the trip might be associated with the anticipated hand-over of power in the secretive regime from the aging Kim to his son.
Shi Yinhong, a professor at Beijing's Renmin University, said that Kim "must need China's help in reducing tensions and ensuring a good environment for the succession of his son."
The visit might also signal that North Korea is prepared to return to six-party talks on its nuclear program hosted by China. North Korea also badly needs humanitarian assistance after a series of economic blunders, as well as poor harvests and damage to cropland caused by recent flooding.
Unlike his last trip, when preparations were detected days ahead, Kim Jong Il arrived this time with little notice, his train crossing the border into the Chinese city of Dandong at midnight.
The Yuwen Middle School would not confirm Kim's visit Thursday, but a waitress at the Arabic restaurant across the street said, "The area was sealed off from 10.30 a.m. to 11 a.m. in the morning and everybody was saying that Kim Jong Il was there."
The real curiosity of this latest visit was not the North Korean leader but his son, Kim Jong Eun, who reportedly will be introduced to Chinese officials, perhaps a precursor to his being officially named his father's successor.
Chinese analysts believe that the younger Kim, who is in his late 20s, may meet with Xi Jinping, China's vice president and considered the likely successor to Hu. Xi was not among the bevy of Politburo officials who greeted Kim during his May visit, although the North Koreans reportedly had asked to meet him.
Kim Jong Il, who is 68 and in poor health after suffering a stroke in 2008, is expected to announce his successor at a special congress next month of the ruling Workers Party.
"It's likely that Kim Jong Il wants to end the debate on the succession issue" ahead of the congress, said Yang Moo-jin, a professor at the University of North Korean Studies in Seoul. "There's been plenty of succession talk between working-level and senior-level officials in Beijing and Pyongyang where they have failed to reach an agreement. Kim Jong Il now seems to be taking matters into his own hands."
The presence of the younger Kim, who was educated in Switzerland and speaks several languages, might be something of a courtesy call.
"China will have no choice but to deal with Kim Jong Eun," said Shi of Renmin University. "Their regime is traditionally a family dynasty and, like it or not, if you deal with North Korea, you have to deal with their ruler."
The visit comes amid tensions on the Korean peninsula following the deadly sinking of a South Korean warship in March. Seoul has accused North Korea of carrying out an unprovoked torpedo attack. Pyongyang has denied the charge.
The trip comes the day after Carter arrived in Pyongyang to help secure the release of a U.S. citizen imprisoned for illegally entering the country.
Glionna reported from Seoul and Demick from Beijing. Ethan Kim in The Times' Seoul Bureau and Tommy Yang in the Beijing Bureau also contributed to this report.