North Korea's reclusive leader, Kim Jong-il, is making his second visit to China this year in what is seen as an opportunity to present his youngest son and chosen heir to his main ally as he seeks to cement the world's only Communist dynasty. The timing of the visit was surprising as it coincided with a visit to Pyongyang by the former US president Jimmy Carter, who has been trying to secure the release of a Christian activist jailed for trespassing. It had been presumed that Mr Kim and Mr Carter would meet.
Mr Kim, who suffered a stroke in August 2008, last visited China in his custom-made train three months ago and, as usual, neither government confirmed his latest trip.
It was unclear who he would meet but there were reports that the Chinese Vice-President, Xi Jinping, was going to Jilin city in north-eastern China to meet him.
North Korea's economy is in a constant state of near-collapse, and aid from China is said to be keeping the country going. The North's nuclear testing has angered its only significant friend, and China has even co-operated with the United Nations in sanctions against the North.
Teachers at Yuwen Middle School in Jilin confirmed that Mr Kim had visited, although they could not say if he was with his son, Kim Jong-un. Mr Kim's father, the late Supreme Leader Kim Il-sung, attended the school from 1927 to 1930 after his family fled the Japanese occupation of Korea.
Identifying Kim Jong-un is no easy matter. Last year a Japanese television station showed a photograph of what was said to be Jong-un, but which turned out to be a South Korean construction worker.
The Swiss-educated Kim Jong-un was born in 1983 or 1984. Kim Jong-il has asked North Korea's main bodies and overseas missions to pledge loyalty to him, and his son is expected to be granted a key party position next month, when the new ruling Workers' Party leaders are due to be elected.
China is keen to restart six-nation talks involving both Koreas, Japan, the US, China and Russia on ending the North's nuclear programme. North Korea walked away from the talks last year in protest at international condemnation of a long-range rocket launch.
Tensions are high after a South Korean warship sank in March, killing 46 sailors. An international investigation blamed Pyongyang for torpedoing the ships. North Korea denies involvement.
Mr Carter was met in Pyongyang by the North Korean nuclear envoy Kim Kye-gwan and the country's second most powerful nuclear official, Ri Gun, a sign that this visit is as much about North Korea's nuclear ambitions as it is about releasing a US national.
Aijalon Mahli Gomes, 31, a teacher linked to the Evangelist Christian movement, was convicted in April of crossing into North Korea illegally from China. The former president had been expected to leave yesterday but his visit was reportedly set to extend into today.Reuse content