New testimony has emerged about how Chen Guangcheng, a blind human rights activist under house arrest in China, escaped.
According to Hu Jia, a dissident who met Chen in Beijing after his escape, Chen scaled a wall by night to escape from his village in eastern China, past guards and bristling surveillance equipment.
A rights group says Chen has taken shelter in the US embassy, but American officials have not publicly confirmed the reports.
"We talked about how Guangcheng climbed over a high wall in the middle of the night and fell over more than 200
times, and how he wounded himself when he fell down from the wall and couldn't stand up," Hu told Reuters.
"But he kept going and stumbled forward. And, as I remember, he said it took 20 hours to get past all these obstacles to get to the people waiting to meet him," he said.
Photographs provided by Hu showed the pair meeting in Beijing. Hu was detained by police for 24 hours of interrogation on Saturday after meeting Chen upon his arrival in the capital.
Hu said Chen had remained indoors for long periods so the people watching him became accustomed to not seeing him for a few days. After escaping, Chen was then taken to Beijing, 500km away, by supporters.
"It's clearly understood that his supporters took Chen Guangcheng to the safest place, and our understanding is that the safest place means the United States embassy," Hu said.
Reports indicate that Chinese authorities have detained several people suspected of being involved in Chen's escape.
ChinaAid, a Texas-based group, said it "learned from a source close to the Chen Guangcheng situation that Chen is under US protection and high-level talks are currently under way between US and Chinese officials regarding Chen's status".
A senior White House official said on Sunday that President Barack Obama wanted to strike the "appropriate balance" in dealing with the issue.
The president tries to "balance our commitment to human rights" while continuing "to carry out our relationships with key countries overseas," John Brennan, Obama’s top counterterrorism adviser, said on Fox News.
"We're going to make sure that we do this in the appropriate way and that appropriate balance is struck."
Kurt Campbell, the assistant US secretary of state for East Asian and Pacific affairs, arrived in China on an unscheduled visit on Sunday, but did not answer questions about the purpose of his visit, triggering further speculation that Chen has indeed taken shelter in the embassy.
The issue is threatening to eclipse a planned visit by Hillary Clinton, the US secretary of state, in the coming days.
Chen, a self-schooled legal advocate, and his family had been restricted to his village home in Linyi in Shandong province and subjected to relentless surveillance since September 2010, when he was released from jail.
He has exposed forced abortions and sterilisations in villages as a result of China's one-child policy.
Clinton, is due to hold two-day talks in Beijing, starting on Thursday. Timothy Geithner, the US treasury secretary, will be accompanying Clinton for the visit, during which talks will cover mainly economic issues, but also the crisis in Sudan and maritime claims in Asia's seas.
The US has been seeking Chinese help on various diplomatic issues in recent days, particularly on attempting to act as an interlocutor with the North Korean and Syrian governments. Bilateral disputes over trade, China's currency and US relations with Taiwan will also likely be part of the strategic talks.