The State Department does not have an accurate accounting of its laptop computers, including ones meant for classified use, and has failed to encrypt machines as it is supposed to do to protect sensitive information, according to a new report by the department's inspector general.

Inspectors found that 27 laptops, worth $55,000 were missing out of a sample of 334 from four State Department bureaus, the report states.

"Because thecontent and the encryption status of the missing laptop computers are unknown, there is a risk that PII (Personally Identifiable Information) and other sensitive Department information may be susceptible to unauthorized access and use," it says.

While no security breaches were confirmed, the report is critical of the State Department's system for tracking its laptop computers, and recommends changes to improve it.

The report is the latest in a series of developments that cast doubt on the federal government's ability to protect classified and personal data.

In 2006, an analyst from the Veterans Administration took home a laptop computer containing social security numbers and other data for more than 26 million veterans, and it was subsequently stolen in a burglary. The machine was recovered without any apparent data breach.

In March 2008, it became known that State Department employees, most of them contractors, had snooped into the passport files of the three presidential candidates: Sen. John McCain, R-Ariz., Barack Obama and Hillary Clinton, who is now secretary of state.

The latest State Department report also found that the department had failed to meet its own mandate to encrypt all laptop computers containing unclassified or "sensitive but unclassified" information by July 1, 2008, to protect against data breaches.

More than half the machines tested were not encrypted, including some used for classified information.

The Inspector General audited laptop inventories at four department bureaus: Diplomatic Security; Intelligence and Research; Information Resource Management; and Overseas Building Operations. Of the four, only the Intelligence and Research bureau, State's intelligence arm, could account for all its laptop computers.