Nicholas Teausant of Acampo, Calif., was taken off a northbound Amtrak bus overnight near the Canadian border. He has been charged with one count of attempting to provide material support to a foreign terrorist organization.
Teausant is accused of exploring ways to support violent extremist activities since October 2013. He had apparently posted on social networking sites like Instagram that he wanted to conduct violent jihad and be "part of America's downfall," a criminal complaint said.
"I would love to join Allah's army but I don't even know how to start," he posted in May 2013.
In December, Teausant revealed to an informant working with the FBI that he and his friends discussed "hitting Los Angeles on New Year's Eve or New Year's Day, specifically targeting the subway in Los Angeles.
"Don't go to L.A. anytime (soon)," he said in a text to the informant. "Please trust me on this...and if you do go don't use the subway."
But when asked what happened to his L.A. plan about a month later, Teausant said they had been "tipped off." The complaint states that Teausant told the informant that he wanted to fight in Syria and "train fighters in Syria to shoot properly" to support the efforts of the Islamic State of Iraq and the Levant.
The Islamic State of Iraq and the Levant is a breakaway organization from al Qaeda that is considered one of the most brutal groups fighting in Syria's civil war, made up largely of non-Syrian Islamic militants. It has seized several areas in Syria as it fights the government of President Bashar Assad.
The informant questioned whether Teausant was serious about his plans since he had not followed through so far, but Teausant stressed that he was. He even stated that if his mother were to jeopardize his plans, he would kill her.
"Teausant mentioned the possibility of simply tying her up, but stated 'it's just easier to put a bullet in the head,'" the complaint stated.
According to a criminal complaint, Teausant is a student at San Joaquin Delta Community College in Stockton and had been a member of the National Guard, although he was in the process of being discharged for failing to meet basic academic requirements.
If convicted, Teausant faces 15 years behind bars.
The Associated Press contributed to this report.