Washington ? Energy Secretary Samuel Bodman on Thursday dismissed the chief of the country’s nuclear weapons program because of security breakdowns at the Los Alamos, N.M., laboratory and other facilities.

Linton Brooks said he would leave in two to three weeks as head of the National Nuclear Security Administration, a post he held since July 2002.

Bodman said the nuclear agency under Brooks, a former ambassador and arms control negotiator, had not adequately fixed security problems. “I have decided it is time for new leadership at the NNSA,” Bodman said.

Brooks told agency workers in a statement, “This is not a decision that I would have preferred … (but) I accept the decision and you need to do likewise.”

He characterized the demand for his resignation as “based on the principle of accountability that should govern all public service.”

Brooks was reprimanded in June for failing to report to Bodman a security breach of computers at an agency facility in Albuquerque, N.M., that resulted in the theft of files containing Social Security numbers and other personal data for 1,500 workers.

The theft did not become generally known, nor was Bodman made aware of it, for eight months.

Last fall, security at Los Alamos came into question anew. During a drug raid, authorities found classified nuclear-related documents at the home of a woman with top secret clearance who worked at the lab.

That security breach was especially troubling, the department’s internal watchdog said, because tens of millions of dollars had been spent to upgrade computer security at Los Alamos. The lab is part of the nuclear weapons complex that Brooks’ agency oversees.