Updated at 11:15 a.m. ET: Blind Chinese activist Chen Guangcheng is under U.S. protection after a bold escape from 19 months under house arrest, sources told NBC News on Monday, a revelation that looked sure to complicate Secretary of State Hillary Clinton's looming trip to Beijing.

"My sources tell me that Chen is, indeed, under U.S. protection in Beijing.  Now we don't know whether that means he's actually within the walls of the American Embassy compound, or in a diplomatic safe house, but he's definitely in U.S. hands there," NBC News Chief Foreign Affairs Correspondent Andrea Mitchell said on TODAY Monday.

The United States has not given any public confirmation of reports that Chen, who reportedly slipped away from under the noses of guards and surveillance equipment around his village home in Shandong province on April 22, fled to the U.S. Embassy.

Rights group: China, US in talks over blind activist Chen Guangcheng

Chen, a self-schooled legal advocate who campaigned against abortions forced under China's "one child" policy, was held under extra-legal detention in his village home in Linyi from September 2010, when he was released from jail for charges he said were spurious. 

Reuters

Chen's wife, Yuan Weijing, and child did not escape with him, and human rights activists have voiced worry that they and Chen's other relatives might have suffered abuse at the hands of police and officials angry about his escape. 

The questions surrounding the activist are casting a pall over the upcoming high-level meeting in Beijing, which would have been challenging for Clinton and Treasury Secretary Timothy Geithner even without a human rights dispute.

Read more China coverage on our Behind The Wall blog

"There are very delicate negotiations under way ... in advance of Hillary Clinton and Treasury Secretary Timothy Geithner's annual talks this week," Mitchell said.

The May 3-4 Strategic & Economic Dialogue is the last of such annual consultations before political seasons heat up in the United States and China, giving leaders in both countries less flexibility over contentious economic and security issues.

The United States goes into full campaign mode for the November presidential election, while China's ruling Communist Party enters a leadership transition in the fall that has been complicated by a scandal that toppled senior leader Bo Xilai.

Bob Fu, whose religious and political rights advocacy group ChinaAid who has been the chief source of information about Chen, said he had confirmed "intensive talks" between the United States and China began right after the activist took shelter in the embassy.

"I was told the Chinese top leaders have been deliberating a decision to be made very soon," Fu said on Sunday by telephone from Texas. A "Chinese official response (is) expected in the next day or so," he added.

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The European Union, meanwhile, urged China show "utmost restraint" over Chen.

"We call on the Chinese authorities to exercise utmost restraint in dealing with the matter, including avoiding harassment of his family members or any person associated with him," the Delegation of the European Union to China said in a statement. "Human rights defenders should be treated in full compliance with Chinese laws and constitution." 

China has declined direct public comment on Chen's reported escape.

NBC News, msnbc.com staff and Reuters contributed to this report.

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