The Ronald Reagan Presidential Library cannot account for the whereabouts of tens of thousands of artifacts relating to the country's 40th president, FOX News has confirmed.

A National Archives investigation began after allegations surfaced that a former employee was stealing memorabilia from the Simi Valley complex, but the investigation led to the uncovering of the deeper problem, officials told The Los Angeles Times.

• Click here to read the full story in The Los Angeles Times.

The audit of all 12 presidential libraries found that the Reagan Library couldn't locate more than 80,000 pieces of the collection, out of roughly 100,000 items.

The report says "that while control weaknesses varied by library, there was a near universal breakdown in controls at the Ronald Reagan Library which have resulted in the library’s inability to adequately account for and safeguard its museum collection."

The report also says the library "may have experiences loss or pilferage the scope of which will likely never be known."

• Click here to read the National Archives audit report (.pdf).

There is concern that some of Reagan's famous collection of Western-style belt buckles might be missing. At least one archivist stands accused of lifting items from the museum.

The report also details lax record-keeping and poor handling of delicate objects, including stacked paintings and haphazardly stashed sculptures and vases in an earthquake-prone region.

Sen. Charles Grassley, R-Iowa, who also pushed for the audit, called the report's release "a wake up."

"Museum managers need to keep pace with the growing challenges of cataloging and preserving presidential artifacts. These papers, records and other items have historical value and should be safeguarded for the education and benefit of future generations of Americans," Grassley said.