A 37-year-old Georgia salesman has pleaded guilty in federal court to trying to join the Islamic State group.

Leon Nathan Davis told a U.S. District Court judge Wednesday that he bought a one-way plane ticket last fall from Atlanta to Turkey, where he planned to be smuggled into Syria in order to join the Islamic State. FBI agents arrested him at the Atlanta airport Oct. 24.

Davis didn't say why he wanted to join the militant group, but told the judge he understood it was considered a terrorist organization. He faces up to 15 years in federal prison and will be sentenced later.

Davis is among several dozen people in the last year charged with trying to fight alongside the Islamic State and other militants or with lending them material support.