Since 2002, billions of U.S. tax dollars have been spent rebuilding Afghanistan after decades of war. A big chunk of that money pays Afghan soldiers and police.

But it turns out a lot of those troops may not, in fact, exist. On “Full Measure,” we investigate how your tax money is being wasted on “ghost soldiers.”

Here’s my interview with John Sopko, who is the inspector general watching over the U.S. taxpayer billions spent to rebuild Afghanistan.

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Sharyl Attkisson: When you say “ghosts,” what are you referring to? John Sopko: What we’re talking about are policemen, Afghan policemen, Afghan military, Afghan civil servants who don’t exist or they have multiple identity cards and we’re paying their salaries. By “we” I mean the United States and the international community…

For years, multiple audits have shown there’s no way to prove that the money we send for salaries is going to a real live body. And the payroll numbers just don’t add up.

For example, Sopko says, in June 2016 the supposed number of Afghan military and police was 319,595. But an Afghan official told the Associated Press “the best internal estimate” of the real number was “around 120,000.”

Attkisson: This implies fraud, obviously. Sopko: Absolutely. Major fraud. And what’s happening is the commanders or generals or other higher officials are actually pocketing the salaries of the ghosts. And I remember President [Ashraf] Ghani, again, at that time he wasn’t president, saying, “John, you, the United States government, are paying the salary of an Afghan who’s a teacher, he’s a civil servant, he’s a doctor, he is a policeman, and he’s a soldier. And it’s the same Afghan. And he doesn’t exist.” Attkisson: What kind of money are we talking about? Sopko: Hundreds of millions of dollars, we’re talking about, that may be lost.

In multiple letters and audits, Sopko has taken the Pentagon, which manages the money, to task stating, “Persistent reports raise questions regarding whether the U.S. government is taking adequate steps to prevent taxpayer funds from being spent on so-called ‘ghost soldiers.'”

And he says the “ghost” phenomenon extends beyond Afghan and security paychecks to other forms of aid.

Sopko: It’s not just the salaries. We’re funding schools based on the number of students, so if you invent or inflate the number of students, you’re going to be paying more money. On the soldiers and police, we’re paying for extra boots, food for everything else and logistics for numbers that don’t exist. Attkisson: Is there any way to tell who’s taking the money? Sopko: It’s difficult because of the security situation. It’s really up to the Afghans or designing systems for the Afghans to implement.

The Pentagon is implementing a new system of biometrics in Afghanistan, using fingerprints, photos, and blood type. It recently said up to 95 percent of Afghan police and 70 to 80 percent of soldiers are now enrolled. The idea is to dispense with old ghosts, and ensure proof of life among a faraway force funded by U.S. taxpayers.

The Pentagon expects to complete its person-by-person verification of Afghan’s army and police in July.