Inside the 'ghost student' scam that uses identity theft to steal college loans and financial aid

Authorities are investigating a growing scam in which so-called "ghost students" use stolen IDs to enroll in college classes to steal student loans and financial aid.

Murat Mayor has no need for an associate's degree. The 58-year-old business analyst already has a Ph.D. But when he and his son, a high school senior, attempted last fall to apply for federal student financial aid, they learned that an account associated with both of their identities already existed.

Those accounts showed applications to multiple community colleges -- and much more.

"We noticed that there [was] a lot of activity" on accounts created in their names, Mayor said in an interview with ABC News. "There are a lot of applications, loan applications, grant applications ... then we panicked."

Mayor knew immediately that something was amiss. He assumed his identity had been stolen. But he had no concept of the breadth of the scheme that had ensnared his and his son's identity, and he had certainly never heard of the army of digital fraudsters perpetrating the crime.

They are known as "ghost students," and for thousands of colleges across the country, these sophisticated thieves have a become a scourge. The scammers will use stolen or fake identities to enroll in classes online and sign up for Pell grants and loans, then disappear once they get the money -- robbing the federal government of hundreds of millions of dollars and leaving an untold number of victims like Mayor and his son in their wake.