Speculation about a possible visit by a high-ranking North Korean official circulated around the Chinese capital on Monday, after Japan's Kyodo News reported that a special train may have carried Kim through the northeastern border city of Dandong.
Passengers were diverted and services cancelled as the train arrived in Beijing, before video emerged showing a auto driving away under heavy police guard.
A convoy under heavy security is seen passing into the Diaoyutai State Guesthouse in Beijing where top North Korean leaders have stayed on previous trips to Beijing, China.
The South Korean government said it was investigating the reports.
A soldier walks past a television screen showing pictures of President Donald Trump and North Korean supreme leader Kim Jong Un at a railway station in Seoul, South Korea, on March 9.
While many USA officials are skeptical about North Korea following through with any formal meeting, supporters of diplomacy say that even the prospect of talks is an encouraging change. A spokeswoman for the Chinese Foreign Ministry said she was not aware of the situation and had no further comment.
Cavs down Bucks 124-117 in Kevin Love's return
For Miami, Dwyane Wade missed his fourth consecutive game and Hassan Whiteside sat out his fifth straight contest. After not getting a foul called on a third attempt, he finished Cleveland's next possession with a massive dunk.
There was no official word from Chinese or South Korean officials - or from North Korea, which in years past routinely announced visits to Beijing by Kim's late father, Kim Jong Il, only after he had come and gone. Having Kim choose the USA and Trump-which are openly hostile toward North Korea-over China and Xi Jinping for his first foreign foray would have been embarrassing.
White House spokesman Raj Shah said the United States could not confirm reports that Kim was visiting China.
Kim's late father, Kim Jong Il, visited Beijing in 2011.
China watchers like author and blogger Gordon G. Chang said if Kim was indeed in Beijing, "all this talk of China losing influence in Pyongyang is incorrect analysis".
According to Konstantin Pulikovsky, a former Russian diplomat who drew on internal classified memos from Kim's visit to Russia in 2001, the train was staffed by "beautiful lady conductors" and live lobsters were shipped to stops along the route, along with cases of Bordeaux and Burgundy red wines.
It would be his first official trip to a foreign country. China has been one of North Korea's most important allies, but relations have grown chilly because of Kim's development of nuclear weapons and long-range missiles.