China's alleged theft of nuclear weapons technology from a federal laboratory has fueled a growing national security controversy. But much surrounding the case remains a mystery. Here is a look at what is known:
Q: What was stolen and when?
A: U.S. intelligence experts believe China in the mid-1980s obtained critical data about development of "miniaturized" nuclear warheads from the Los Alamos National Laboratory in New Mexico. It's not known exactly what information was obtained.
Q: How did they find out and when?
A: The United States learned in 1995 that China had made an unusually rapid leap in warhead development. A 1988 Chinese document, obtained by U.S. intelligence, and close analysis of Chinese weapons tests prompted U.S. officials to suspect China had developed a warhead similar to the W-88 miniaturized warhead developed at Los Alamos.
Q: What is the national security significance?
A: The development has helped China equip a missile with multiple warheads capable of striking more than one target. A special CIA task force has been asked to give a detailed analysis of the security implications by April.
Q: What was the U.S. response?
A: The FBI began an investigation in early 1996, focusing immediately on the federal weapons labs, especially Los Alamos, where the W-88 was designed. It narrowed the list to five prime suspects and eventually to a Taiwan-born computer scientist at Los Alamos.
Q: Who is Wen Ho Lee?
A: Born in Taiwan in 1939, Lee is a naturalized U.S. citizen who has worked at Los Alamos since the 1970s. The computer scientist became an early target of the FBI investigation in 1996, but apparently was directly confronted only recently.
Q: Why was Lee singled out?
A: That is still not totally clear, except that he was ethnic Chinese, that his work in the 1980s reportedly involved warhead computer codes and trigger mechanisms, and that he had made at least one trip to China in the 1980s, along with his wife, to attend a conference. Lee and his wife live in a suburb of Los Alamos where neighbors describe him as friendly and unassuming. Associates say he had no direct involvement in warhead design or access to blueprints.
Q: Why was Lee fired and has he been charged with a crime?
A: Lee was fired March 8 after he had been interviewed for several days by the FBI. Lee has not been charged with any crime. He was fired for failing to inform his superiors of contact with "a sensitive country," failing to "properly safeguard classified material" and "apparently attempting to deceive" officials about security-related issues. He was said to have failed a polygraph in February, but no details on why he failed are available.
Q: Why did this investigation take three years and why did it surface now?
A: Law enforcement sources say investigations involving espionage often takes years. This case was made more difficult because the alleged offense took place so long ago, and investigators were trying to re-create what may have happened in the mid-1980s. The FBI sought but could not get approval for tapping Lee's telephone, and only in recent weeks did the FBI confront Lee directly. The dismissal occurred two days after The New York Times - though not naming Lee - detailed the espionage case. Energy Secretary Bill Richardson called the timing of the news report and the dismissal a "coincidence."
Q: Was the investigation given adequate priority?
A: The White House insists the investigation was aggressively pursued beginning in 1996. When more detailed information about security problems at the labs were reported in mid-1997, new security measures were imposed within six months. Critics charge that security problems continued well into 1998 and may persist even today. And they question why Lee was allowed to remain in a sensitive job with top security.
Q: How has security been approved at the national labs?
A: Workers in sensitive jobs now are subject to polygraph; increased screening is required of visitors, with background checks made on foreign visitors from "sensitive countries" such as Russia and China; counterintelligence officers are assigned to each lab; and a new director for counterintelligence was hired at the Energy Department headquarters, reporting directly to Richardson.
Q: How secure are the labs?
A: Richardson insists the security changes that were made "are addressing the problem" but that he has "no illusions" that China will continue to try to obtain U.S. secrets. Critics are still not sure security is what it should be at the labs. A 700-page report, which GOP lawmakers want largely made public, details worrisome security lapses, the critics argue. How much of the top-secret report will be made public remains to be seen. USA TODAY reported Wednesday that briefing materials and other internal reports it has obtained show the Energy Department requested at least 19 FBI investigations last year involving possible security breeches and that 4,000 "reinvestigations" need to be done on department personnel whose security clearances are more than five years old.
Q: The political fallout?
A: Although the suspected Los Alamos espionage dates back to the Reagan administration, Republican critics have used it to challenge President Clinton's broader policy of engagement with China. GOP presidential hopefuls have accused the Clinton White House of not pursuing the investigation promptly.
Q: What's next?
A: Intelligence committees of both the Senate and House have promised to pursue the issue of weapons lab security. Clinton is expected to raise the espionage issue when Chinese leaders visit next month. And sometime soon, a special House committee on technology losses to China hopes to make public most of its 700-page findings, including details about the Los Alamos investigation. In Los Alamos, there is no indication that Lee will be prosecuted anytime soon, though the investigation continues. Lee has not been seen publicly, but reportedly has hired a lawyer.