The recent sting by the Government Accountability Office exposed lax security procedures by the Federal Protective Service, the agency that guards more than one million workers at 9,000 federal buildings nationwide.

Mark Goldstein, who led the investigation, told senators yesterday that his team carried bomb-making materials into 10 high-security federal buildings in the past year. The materials could be purchased in stores or online and cost roughly $150.

Once inside, investigators assembled bombs in restrooms and then walked around with them, undetected. In only one instance did a security guard question an investigator carrying suspicious materials.

In three or four locations, Goldstein said, "guards were not even looking at the screens that would show materials passing through. If a guard had been looking, they would have seen materials not normally brought into a federal building."

He said the Federal Protective Service was "an agency in crisis."

The GAO's final report will conclude that many contract guards employed by the service lacked at least one certification in CPR, first aid, or firearms training or proof that they had not been convicted of domestic violence, according to the Senate Homeland Security and Governmental Affairs Committee, which heard the GAO's preliminary conclusions yesterday.

Many guards also lack proper training on operating metal detectors or X-ray equipment, the report found.

Committee chairman Joe Lieberman (I., Conn.) said he wanted to publicize the initial findings to quickly address concerns about the FPS's performance.

"That's about the broadest indictment of an agency of the federal government that I've heard, and it's not pleasant to hear it," he said.

Most of the concerns surrounding the FPS involve money and staffing. It draws revenue from the tenants of the federal buildings. It has 1,236 full-time employees and employs about 13,000 private security guards on contract.

The service follows Justice Department security guidelines established after the 1993 bombing of the Alfred P. Murrah Federal Building in Oklahoma City. The highest security category, Level 5, is reserved for high-profile facilities not guarded by the service, including the White House and CIA headquarters.

The GAO team entered 10 Level 4 facilities that house more than 450 federal employees and offices for the Departments of Homeland Security, Justice and State. The buildings also house agencies that permit unscheduled visits, including the Social Security Administration and the IRS.

Gary Schenkel, director of the FPS, told lawmakers: "It's purely a lack of oversight on our part. We were fairly distracted in previous years . . . but we realize that our core mission is to protect federal buildings."

The FPS could not properly manage its contracts with private security firms, he said, and has lacked money and staffing since becoming part of U.S. Immigration and Customs Enforcement in 2003.

Lieberman said his committee would introduce legislation to reauthorize the FPS, give it more funding, and instruct Homeland Security Secretary Janet Napolitano to reorganize the agency while developing new staffing and training plans.