Heads continue to roll at the troubled Los Alamos National Laboratory. Twin scandals involving fraud and lax security forced the atomic lab's director, John Browne, to resign late last week. On Tuesday, the lab announced that the security officials at the heart of the imbroglios have been demoted. Stan Busboom and his deputy, Gene Tucker, were charged with keeping the country's most important nuclear lab secure. And they were supposed to prevent employees from stealing equipment and misusing government funds. But Los Alamos suffered from chronically lax security. Many of the guards didn't even carry guns. Millions of dollars' worth of equipment was stolen or lost, including hard drives that almost certainly had classified information on them. And employees tried to use lab money to buy personal goods, from gas grills to fancy cars. Then, when Steven Doran and Glenn Walp -- the former police chiefs Busboom recruited to look into these problems -- reported what they knew to Department of Energy investigators, the two were fired, almost on the spot. "(Busboom and Tucker) have been lying for God knows how long -- about property issues, about their accountability, and about crime and corruption in the lab. Now they're paying for it," Doran said. "You can only avoid the system for so long." Project on Government Oversight investigator Peter Stockton, a longtime critic of the lab's management, welcomed the news of the demotions. "It's clearly a step in the right direction," Stockton said. "These were the guys responsible for the security of the lab, both financial and physical. They left nuclear material vulnerable to terrorists. Their (demotions) are more significant substantively than (lab director) Browne stepping down." Both Doran and Stockton predicted that more Los Alamos officials would be fired, demoted or forced to resign. Indictments on obstruction of justice charges are also likely. What Busboom and Tucker will do next is unclear. They have not yet been given new assignments at the lab. Los Alamos' security has been iffy for years. In a 1997 exercise, for example, soldiers managed to roll a cart filled with nuclear materials out of the facility without being questioned. In 2000, nuclear scientist Wen Ho Lee pled guilty to mishandling classified information. Such lapses continue today, Doran asserted. Certain guards are allowed to carry guns, he said. And investigations are constantly being stymied. On Sept. 19, Doran said Busboom told him his "career would end" if lab managers felt that he had tarnished their relationship with the FBI, inspector general or U.S. attorney. In November, an employee from the lab's "X Division" -- the nuclear weapons physicists -- was spotted carrying a roll of plans from the facility to his car. When Doran tried to ask the employee about the papers' contents, one of Busboom's deputies tried to prevent it. Doran eventually questioned the employee anyway. It turned out the papers were blueprints of the worker's home. While national security wasn't compromised, "the incident shows the attitude about security there," Doran said. "General Motors guards the spark plugs at their factories better."