Mohammed Hamzah Khan, a 19-year-old from the Chicago suburbs, was reportedly arrested by FBI agents Saturday evening at the city’s O’Hare International Airport for allegedly attempting to travel to Turkey and join the Islamic State group. Khan was charged with a single count of attempting to provide material support to a foreign terrorist organization, according to the U.S. Attorney’s Office of the Northern District of Illinois, CNN reported Monday.

Described as “slight and bearded” by CBS News, Khan appeared Monday in federal court. A judge ordered him held until at least Oct. 9, when he will have a detention hearing.

After arresting him, FBI agents searched his home and found documents showing support for the militant group also known as ISIS that are believed to have been written by the teen, as well as a letter to his parents explaining his belief that he was obligated to join ISIS as it had established a caliphate. He also wrote about his disgust with Western society, according to the Associated Press.

"We are the lions of War," he allegedly wrote. "My nation, the dawn has emerged."

Khan was allegedly hoping to fly to Istanbul by way of Vienna then travel over the Syrian border by ground. He faces a maximum of 15 years in prison and a $250,000 fine if he is convicted of traveling abroad to support terrorism, according to CBS.