China's likely next leader on Monday cancelled a scheduled meeting with Denmark's visiting prime minister, fuelling speculation about his whereabouts after he also failed to meet Hillary Clinton last week.
The incident came at a highly sensitive time with China's communist leaders preparing to hand over to a new generation, expected to be headed by Vice President Xi Jinping, at a congress due to take place in the coming weeks.
China's foreign ministry had flagged a meeting between Xi and Denmark's Helle Thorning-Schmidt to the media last Wednesday -- the same day Xi cancelled talks with the visiting US secretary of state, Singapore's prime minister and a Russian official.
But the Monday meeting scheduled at 4:00 pm (0800 GMT) did not take place and Denmark's embassy in Beijing said there were no plans for the pair to get together during Thorning-Schmidt's visit.
The latest cancellation followed a frenzy of speculation about Xi's health on Chinese-language websites based overseas, one of which said that he had been involved in a car crash -- a report it later retracted.
The site, Boxun, blamed the error on "leftists... trying to create rumours" and said that Xi in fact had only some minor health problems. Other overseas media reported that he was suffering from back problems.
In an indication of the sensitivity surrounding the issue, Danish embassy spokesman Ming Ou Lu refused to confirm or deny that a meeting between the two had even been scheduled.
China's foreign ministry spokesman Hong Lei also evaded repeated questions about Xi's absence at a daily briefing for foreign media on Monday, saying that he had "no information" to provide.
"Obviously the Chinese authorities are also concerned about any news that may create an adverse speculation concerning the leadership succession process," said Joseph Cheng, China scholar at Hong Kong's City University.
"They are so worried and sensitive. (The result is) that they have not been acting sensibly."