A special train believed to be carrying Kim Jong Un has departed Beijing after a two-day visit by the North Korean leader to the Chinese capital.
Mr Kim could not be seen but he was presumed to be on board the long train as it crossed on elevated tracks over a busy Beijing street and headed towards eastern China and the border with North Korea.
Mr Kim's trip to China - his fourth in the past 10 months - is believed to be an effort to coordinate with his only major ally ahead of a possible second summit with US President Donald Trump.
It comes after US and North Korean officials are thought to have met in Vietnam to discuss the site of the summit.
Details of his visit have not been released, but Mr Kim reportedly met Chinese President Xi Jinping.
Earlier, Mr Kim's motorcade headed out to an unannounced destination and returned about an hour later.
South Korea's Yonhap News Agency said Mr Kim visited a technology development zone and spent around 20 to 30 minutes touring a factory.
North Korean and Chinese state media announced his visit shortly in advance of his arrival in Beijing, in a break with standard protocol dictating such trips are only confirmed after they happen.
However, neither side has provided details of what he has done since arriving aboard his personal armoured train on Tuesday morning.
It is understood Mr Kim met Mr Xi for about an hour on Tuesday and later attended a dinner at the Great Hall of the People in central Beijing hosted by Mr Xi and his wife. Mr Kim was accompanied by his wife, Ri Sol Ju.
At Tuesday's daily foreign ministry briefing, spokesman Lu Kang said Beijing remains supportive of efforts to end tensions over US demands for a halt to North Korea's nuclear and missile programmes.
Mr Kim's visit is also seen as part of an effort to win Chinese support for a reduction of UN sanctions imposed over his nuclear weapons and ballistic missile programmes, which have severely impacted his country's already ailing economy.
While North Korea has not conducted any launches or detonations in more than a year, it has displayed no real intention of abandoning the programmes that are seen as guaranteeing the hardline communist regime's survival.
Mr Kim's visit also came after he expressed frustration in his annual New Year's address over the lack of progress in negotiations with Washington since the Singapore summit with Mr Trump in June.
He said that if things do not improve - meaning that if sanctions relief and security guarantees are not in the offing - Pyongyang might have to find "a new way" forward.
- Press Association