Chinese rights activist Chen Guangcheng is in the US embassy in Beijing, his friend and fellow dissident Hu Jia said on Monday, in a case that threatens to rile China-US ties.
Hu, who was detained over the weekend for questioning in the affair, also said Chinese security officials indicated that Chen had met with US ambassador Gary Locke since the activist's dramatic flight from house arrest.
"He is in the embassy," Hu, who had met with Chen after his escape, told AFP when asked whether he could confirm rumours of Chen's whereabouts.
"They asked when Chen Guangcheng met with ambassador Gary Locke," he added.
"So it seems very clear that he has met with the American ambassador. I had no way of answering. I do not know what is going on inside."
"But when I heard this I was very surprised and excited," Hu added.
Chen, a self-taught lawyer, fled house arrest in Shandong province on April 22 with the help of supporters from under the noses of dozens of guards and subsequently recorded a video alleging abuses against him and his family.
Since then, rumours have swirled that Chen had made it to safety in the US embassy, but the embassy and State Department officials in Washington have refused to confirm or deny them.
China will no doubt be extremely upset about the United States harbouring a fierce critic of its government, and the sensitive situation threatens to become a major diplomatic entanglement.
It comes as US secretary of state Hillary Clinton and treasury secretary Timothy Geithner are due in Beijing on Thursday for an annual round of wide-ranging talks on the often-testy China-US relationship.
Chen, 40, won worldwide acclaim for exposing forced sterilisations and late-term abortions under China's "one child" policy, and for using his legal knowledge to help people battle a range of other perceived injustices including land grabs.
He and his family were put under round-the-clock house arrest after he completed a four-year jail sentence in September 2010.
He has said he was being punished for defiantly continuing to speak out and that he and his family members had suffered beatings and other brutal treatment at the hands of local officials in what he has called an illegal house arrest.