The former head of the Energy Department's nuclear weapons program told Congress yesterday that he accepts "some responsibility" for failing to take quick action over allegations of Chinese espionage at U.S. national laboratories.

But Victor H. Reis, the only senior official who has lost his job because of the alleged security breaches, told the House Armed Services Committee that plenty of others share the blame.

"You certainly will find people who didn't do their job as well as they might have," he said, listing "the directors of the laboratories, the head of intelligence, counterintelligence at [the Department of Energy], the people within the FBI -- you could go on forever."

Reis's testimony comes as Energy Secretary Bill Richardson is weighing disciplinary action against various officials based on the findings of a DOE inspector general's report on the handling of Wen Ho Lee, a scientist at Los Alamos National Laboratory who has been under investigation since early 1996 for allegedly spying for China.

Lee continued to have access to classified information until he was fired in March for security violations. But as several House members noted yesterday, senior DOE officials could have changed his job and limited his access to secrets more than a year earlier, in mid-1997, when they were told by FBI Director Louis J. Freeh that the bureau no longer believed Lee should remain in his post.

Reis was assistant secretary of energy for defense programs from 1993 until late last month. He conceded that when he first became aware of the allegations of spying, "I could have pressed harder" for tightening security. But, he said, he thought the department's intelligence and counterintelligence officers, "who were basically in charge of that, were doing it well."

Later, he learned that the FBI was investigating an employee at Los Alamos, but "I was never told the name of the individual," he said.

Reis has said he resigned June 25 because of disagreements with Richardson over reorganization of the nuclear weapons complex. Some Energy Department officials believe he may have been on the secretary's list for disciplinary action.

Yesterday, Reis told the committee he did not support Richardson's naming of a "security czar" to solve the department's security problem.

Reis also warned that too much emphasis on security could end up harming national security. "I'm concerned, frankly, that if we spend all our time worrying about guards and gates and that sort of thing, we'll forget that what we're really talking about is maintaining the nuclear weapons and maintaining them indefinitely, hopefully without nuclear testing," he said.

Reis said the answer was to build concern about security into the minds of all DOE scientists and lab employees. "Security, like safety, then becomes part of the team that is focused on the mission, not entrusted to an external group that is looking to play `gotcha,' " he said.