Why has Xi disappeared?

Chinese Vice Premier Huang Ju lectured Chinese bankers in early 2006 on the importance of government control over state banks. Then he dropped from sight for nearly two months before a Chinese official said Huang had been unwell and was convalescing.

BEIJING — Ten days, and still no sign of Xi Jinping.

China’s president-in-waiting has yet to resurface after cancelling appointments with foreign leaders and disappearing from public view. But late Wednesday he was mentioned in state-run media, which said he gave his condolences to the family of a long-time Communist Party official who died last week.

The reference to Xi — the first since Sept. 5 — appeared online in the state-run China News wire service, and it was repeated in several additional state-run outlets Thursday morning. They listed his name as one of several top leaders, including current President Hu Jintao, who passed along condolences after the death of a retired Guangxi region official named Huang Rong.

Huang died Sept. 6, one day after Xi’s first cancelled meeting with visiting U.S. Secretary of State Hillary Rodham Clinton.

Since then, Xi’s disappearance has spawned endless speculation, just weeks before a sensitive once-in-a-decade leadership transition where he is supposed to take over the country’s reins.

Rumors about his absence continued Thursday, with a host of fresh news reports and unnamed officials supporting conflicting theories: a back problem, heart attack, swimming injury, car crash, a studious desire to seclude himself to adequately prepare for the coming party meeting.

The heart attack theory is favored by some experts because it’s severe enough to prevent Xi from doing a photo-op or public appearance but not so serious that it would put his ascension to China’s top post in question.

“It seems the most likely to me because the activity level of China’s other leaders seems to be quite normal the past few days. They’re all making their appearances, giving their speeches,” said Bonnie Glaser at the Center for Strategic and International Studies.

One man — who, like Xi, is part of the group of children of revolutionary leaders, commonly called China’s “princelings” — said Xi’s mother told a concerned visiting princeling that her son was not feeling well but had not suffered anything serious. The man spoke on condition of anonymity because of the party’s current crackdown on discussion of Xi.

Domestic politics could be thrown into turmoil if succession truly becomes an issue.

Because of difficult balancing of opposing party factions that goes into picking China’s leaders, the top leader is often negotiated years in advance in secret. And unlike countries such as the United States, there is no clear plan for who replaces a leader who dies or becomes incapacitated — especially in rare moments of transition like this.

“The party doesn’t have mechanism to handle such kind of succession crisis properly,” said Li Datong, a former editor of the state-run China Youth Daily and now a political analyst.

The era of total-control leaders like Mao Zedong or Deng Xiaoping, in which one official could decide the direction of the entire country, has given way to a period of consensus rule of a small council of party elites, each with their own power base. The health of that small group of leaders is shrouded in extreme secrecy, a practice rooted in history.

When then-Premier premier Li Peng disappeared for weeks in the 1990s, officials said he had a cold — an excuse later confirmed to be a cover-up for a heart attack. When rumors swirled last year that former top leader Jiang Zemin had died, authorities shot them down with an official statement through the Xinhua News Agency.

Washington Post special correspondent Zhang Jie contributed to this report.