The nation watched as the dramatic Thursday arrest unfolded last week as authorities finally tracked down the culprit behind the classified Pentagon documents leak.

And no, it wasn’t some foreign spy nor part of a big espionage agency that we’re all familiar with. Instead, it was a 21-year-old US Air Force National Guardsman who worked as an Information Technology Specialist—Cyber Transport System Journeyman. An Airman 1st class based out of Otis Air National Guard Base near Providence, Rhode Island.

The Culprit

During a Thursday press briefing, US Attorney General Merrick Garland named Airman Jack Teixeira, who was assigned to the 102nd intelligence wing of the Massachusetts National Guard. This particular unit specializes in intelligence support across the US armed forces, therefore, maintains a trove of highly classified documents.

After a weeklong investigation, the Federal Bureau of Investigation (FBI) agents ultimately traced the “unauthorized removal, retention, and transmission of classified national defense information” to Teixeira.