U.S. tax dollars may be paying for "ghost workers" on the Afghan National Police payroll, which receives a significant amount of its funding from the U.S., according to a letter from the Special Inspector General for Afghanistan Reconstruction to military commanders in Afghanistan.

"I am writing to express my concern that the U.S. may be unwittingly helping to pay the salaries of non-existent members of the Afghan National Police," Inspector General John F. Sopko wrote in the Feb. 19 letter.

ANP salaries are funded by the Law and Order Trust Fund for Afghanistan, or LOTFA. Of the $3.2 billion international donors have paid into LOFTA since 2002, the U.S. has paid 38 percent, or $1.2 billion.

"There is a very significant amount of U.S. taxpayer money at stake in this program," Sopko wrote.

The possibility of ghost workers came up repeatedly during a November trip to Afghanistan, Sopko said.

During that visit, Sopko discussed the issue with Combined Security Transition Command-Afghanistan officials, who said they aren't aware of intentional false payments but that CSTC-A is working with the Afghan Ministries of Interior and Defense to improve accountability for both money and personnel records.

"While we have made significant progress working with the [Ministry of Interior] over the last several years, our recent efforts uncovered discrepancies in the reconciliation of personnel and payroll records," U.S. Army Maj. Gen. Kevin Wendel, commander of CSTC-A, wrote in his response to Sopko's letter.

CSTC-A helped reconcile 54,000 erroneous identification numbers in the database used to manage ANP payroll, which could have allowed to ghost payments. Commanders also implemented a financial agreement with the Afghan ministries to improve their accounting transparency, performed a financial audit and threatened to withhold some LOTFA funding until the ministries made recommended changes.

"While CSTC-A’s own recent actions are positive steps, I remain concerned that we lack an adequate understanding and oversight of how U.S. funds flow from LOTFA through the Afghan banking system to their destination in the hands of legitimate ANSF personnel," Sopko said.

His office is currently auditing ANSF and ANP personnel data and salaries.

The European Commission is also withholding some of its LOTFA funding over concerns about financial mismanagement, including ghost workers, Sopko said. The commission will release the money when Afghan ministries have stronger controls to make sure LOFTA funds are spent properly.

SIGAR's concerns over ghost payments go back to a 2011 audit, which found neither the United Nations Development Program or the Afghan Ministry of Interior could verify LOTFA payroll data.