Kim Jong Eun, shown in September. (AFP)

The fast-spreading rumors, quickly deleted by China’s Internet censors, said that North Korean soldiers had taken over the state-run television station. They also claimed that Chinese troops were heading to the North Korean border to stem the likely flow of refugees.

Since the rumors started flying Wednesday afternoon, U.S. government officials have found no reason to believe they are true.

“There has been no movement among Chinese troops around the border,” said one U.S. official, speaking on the condition of anonymity to discuss sensitive information.

Still, the rumors — and the speed with which they spread — underscored just how little is known about the world’s most opaque government. Experts and outside analysts can only guess at the age of heir Kim Jong Eun, who is trying to consolidate power in the wake of father Kim Jong Il’s death. (He might be 28 or 29.)

They also have little sense of whether Kim Jong Eun is holding power, sharing power, or potentially fighting for it. Even a major power struggle in Pyongyang could be kept under wraps — certainly for hours, possibly for days. North Korea managed to keep Kim Jong Il’s death a secret for some 52 hours before telling the outside world.

The latest rumors spread on Weibo, a microblogging service that is often described as the Chinese version of Twitter. The rumored coup sparked tens of thousands of comments, and Chinese authorities blocked all messages with certain keywords, like “North Korean military coup” or “North Korea coup.”

View Photo Gallery: A rare look inside North Korea as seen by photographer David Guttenfelder.

According to some of the rumors, Kim Jong Eun’s uncle — Jang Song Thaek — had helped lead the military uprising. Another version of the story said that the military was going to install Kim Jong Nam, Kim Jong Il’s oldest son, as the new leader. Kim Jong Nam would create a “pro-China regime.”

Said one commenter: “Rumors said North Korea just had a coup, Kim Jong Eun has fallen from power. ... if there is really a coup, how will China respond? to protect the old or support the new? ... I think North Korea will be reunited with the South and embark on the democracy road. Just like East Germany reunited with West Germany.”

Another commenter said: “Can such a good thing happen? I should open a bottle of wine to celebrate tonight.”

Online users also made note of the rapid deletion of posts. China is North Korea’s most important ally and economic partner, and it has pushed for stability amid Pyongyang’s delicate power transfer.

Staff researcher Liu Liu contributed to this report.

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