The Taiwanese-American nuclear scientist at the centre of an alleged spy scandal has been fired by the United States Government.
In a move to quell rising anger in Congress over failure to contain the reported theft of nuclear secrets, Energy Secretary Bill Richardson dismissed the researcher, Lee Wen-ho, from his job at the Los Alamos laboratory in New Mexico.
The firing is unlikely to prevent Congress from holding emergency hearings into the espionage claims - probably as early as next week.
It also suggests authorities have insufficient evidence to charge Mr Lee or anyone else.
Mr Lee, a University of California employee contracted since the 1980s to Los Alamos - America's most important nuclear weapons development centre - had failed a recent polygraph test and was refusing to co-operate with investigators, officials said.
The Energy Department said he was fired for failing to tell his superiors about 'contact with people from a sensitive country' as well as 'specific instances of failing to properly safeguard classified material and, apparently, attempting to deceive the laboratory about security-related issues'.
Mr Lee's wife, a laboratory employee, is also under suspicion, according to reports.