WASHINGTON (CNN) -- A series of embarrassing incidents on federal property across the country, including the theft of a trailer of surveillance equipment from an FBI parking deck, is being blamed on budget cuts at the agency charged with securing federal grounds.

A Federal Protective Service officer trains with a paintball gun. The agency has lost staff since 2004.

"We're seeing the near collapse of the Federal Protective Service," said Rep. Eleanor Holmes Norton, D-District of Columbia, who leads the congressional subcommittee that oversees federal buildings.

The service's budget and staff have been cut since it became part of the Department of Homeland Security in March 2003, according to the nonpartisan Government Accountability Office.

"I think that FPS is less able to do its job than ... in the past, primarily because of budgetary restrictions that have occurred, and that has forced them to slash their workforce" GAO investigator Mark Goldstein said.

"There are 756 uniformed federal officers to oversee the 8,800 buildings" under the agency's watch, he said.

A preliminary GAO report contained these findings:

• A man died at a vacant federal complex in Kansas City, Missouri, and his body was not found for three months. Watch scene of body's discovery »

• Twenty-two guns were stolen from a federal building in Atlanta, Georgia. A private security guard employed at the building was convicted of participating in the theft.

• A surveillance trailer with $400,000 worth of high-tech equipment was stolen from the parking garage of a federal building in Los Angeles, California.

CNN has learned the trailer was stolen from the Los Angeles FBI field office in May. Contract guards watched the theft on surveillance cameras but did nothing to intervene and did not report the incident for three days, according to an incident report confirmed by the FBI and Norton.

The trailer was recovered with some of the equipment intact. The FBI investigation is still open.

In Kansas City, Eric L. Howell, 27, who had been homeless from time to time, died in a vacant government building sometime in summer 2007. His body was found months later by a government real estate agent showing the property to a prospective buyer. The cause of death could not be determined.

FPS director Gary W. Schenkel defended his agency, telling CNN the incidents cited by the GAO were "taken out of context."

"FPS does not refute that these incidents took place, but I do believe that additional background information shows that FPS and its contract guards acted according to the established mission guidelines and standards," Schenkel said.

He said the trailer was taken by "a government contractor with frequent access to the parking deck" and blamed the FBI for taking "three days to notice and report that its own trailer was missing."

In regards to the Kansas City case, Schenkel said the Government Services Administration building in question "was not on the GSA list," and FPS wasn't being paid to guard it.

But critics say that's just the point -- because of funding cuts since it was made a part of the Homeland Security Department five years ago and an unusual pay-for-service arrangement to compute its current budget, FPS is unable to adequate provide security for government properties.

Before the creation of the Homeland Security Department in 2003, the Federal Protective Service was part of the Government Services Administration, which manages thousands of federal properties across the country, functioning as landlord to hundreds of federal agencies.

While part of the Government Services Administration, the Federal Protective Service had a larger budget and more agents. But its workforce has been cut 20 percent since 2004, the year after the agency became part of Homeland Security. FPS is funded through a complex formula based on the square footage of the property that Government Services controls.

"Everyone was proud the day it was announced that Homeland Security was going to be formed, and there were talks that FPS was going to be absorbed. ... It's been downhill ever since," said David Wright, president of Local 918 of the American Federation of Government Employees, the FPS union.

He said FPS has never been taken seriously within Homeland Security.

"We were at the bottom of the food chain, so there's a real disregard for Federal Protective Service within our parent agency," Wright said.

Last year, Congress required Homeland Security to add 150 officers to the service, but the department still will rely on about 15,000 contracted private security guards for the bulk of the policing at federal buildings, according to the GAO, Norton and the union.

Contract guards are generally less expensive than federal officers, but they lack the training of FPS officers, and in many jurisdictions, they have no power to arrest or detain suspects, Goldstein and Norton said.

"Unless the government is prepared to have a private army or a public army of guards, which would be astronomically expensive, we're going to have to find the right mix of private guards to do security in less risky areas and then have more highly trained guards perhaps in higher security areas," Homeland Security Secretary Michael Chertoff said.

Norton compared the decline of the Federal Protective Service with the shortcomings of the Federal Emergency Management Agency revealed by Hurricane Katrina in 2005.

"Interestingly, both happened when they were transferred to the Department of Homeland Security," Norton said.

"I can't say honestly to anybody who asks that 'Now that the Federal Protective Service is in the Homeland Security Department, you're better off.' You're worse off." E-mail to a friend

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