The National Security Agency, the supersecret eavesdropping agency, working with the Federal Bureau of Investigation and other intelligence organizations, led an operation to plant bugs in a Boeing 767 used by the president of China while it was in the United States for refitting, officials said. The listening devices were quickly discovered, and the Chinese government disclosed the incident early last year.

United States officials have never previously acknowledged the bugging operation, and the Bush administration still publicly declines to comment.

Intelligence officials say they are trying to determine whether the Chinese found out about the operation as a result of an F.B.I. security breach that was disclosed last week with the arrest of Katrina Leung, who officials described as a Chinese double agent, and James J. Smith, a former F.B.I. agent in Los Angeles who was her contact at the bureau.