U.S. officials uncovered a fraud scheme that resulted in almost $160,000 being stolen from an embassy in eastern Europe over a five-year period, according to a new State Department report.

The fraud was little more complicated than stealing from a cash register, but poor security controls at the U.S. Embassy in Georgia allowed it to continue from 2010 to 2014. In total, $159,700 was lost, "likely due to the misappropriation of cash" from the retail store safe by a former employee, according to an audit. The loss of funds was hidden for years because the thief deleted receipts from the accounting records in order to cover up the shortages.

"The deleted transactions were cash sales, and the deletions often occurred many weeks or months after the dates of sale," the State Department's Office of Inspector General explained.

The identity of the thief was obscured by the number of people who had access to the accounting software. The inspector general noted that the commissary employees, as well as the government employees who comprise a board that oversees the embassy employee association, all used the same administrator account to access the accounting software. The scam started small, with $8,700 stolen in 2010. That figure rose to $46,100 by 2012.

Investigators "could not determine" who carried out the fraud, so the inspector general was confined to outlining proposals for preventing it from happening in the future, such as limiting the cash on hand at the commissary.