LOS ANGELES (CBSLA.com) — A National Guard reservist has been arrested at the Canadian border in Washington for allegedly trying to aid al-Qaida in a plot to attack a Southland subway.

Nicholas Teausant, 20, of Acampo, Calif., was charged Monday with attempting to provide material to support a foregoing terrorist organization, the U.S. District Attorney’s Office said. He made his first appearance in a federal courtroom in Seattle Monday afternoon.

Teausant was arrested at the Canadian border “with the intent of continuing to travel to Syria to join the Islamic State of Iraq and Syria, a foreign terrorist organization more widely known as al-Qaida in Iraq,” officials said.

He allegedly began planning the attack late last spring with the intent of carrying it out with the use of an unknown type of explosive on New Year’s Eve or New Year’s Day, a criminal complaint said. He allegedly posted numerous other ideas online for terrorist activities, saying he wanted to see the United States’ downfall. He also said he wanted to join the fight in Syria with known terrorist organizations there.

Teausant allegedly told an FBI informant online that the New Year’s subway bombing had been canceled because they had been “tipped off.”

The informant put the alleged would-be terrorist in contact with a mentor, who was actually an undercover federal agent. That undercover mentor gave Teausant the green light to travel to Syria. Teausant boarded an Amtrak train bound for Seattle Sunday night and then got on a bus. When the bus was about to cross the border into Canada federal agents stopped it, questioned Teausant and arrested him.

The college student has been charged with one count of attempting to provide material support to a foreign terrorist organization. If convicted, Teausant faces up to 12 years in prison.

Court documents say Teausant is a student at San Joaquin Delta Community College in Stockton and a member of the National Guard, who never underwent basic training because he didn’t meet academic requirements.

“He’s not a terrorist. He’s not evil,” Teausant’s mother said Monday, while sobbing.

CBS2/KCAL9 also spoke with the suspect’s grandmother, Virginia Teausant, by phone the same day. She said he “did join something, a Muslim or something, a religion, and we were really surprised by that and not happy about it.”