Kabir led Santana and Deleon to convert and join the Taliban, eventually leading to membership in al-Qaeda, the criminal complaint alleges. Santana recruited Gojali, the fourth man, to join them for the trip abroad to train as terrorists.

Santana tipped off authorities about his militant inclinations when a customs officer at the border with Mexico questioned him about the jihad magazine "Inspire" he was carrying into the United States.

He allegedly engaged in chat conversations with an FBI "online covert employee" and confirmed his desire to join al Qaeda.

An unnamed "confidential source" working for the FBI won the trust of Santana and Deleon, according to the complaint, spent time with them and recorded many of their conversations.

"Santana and Deleon told a confidential source...that they planned to travel to Afghanistan to engage in "violent jihad," the FBI and U.S. Attorney statement said.

Their conversations with the confidential source revealed details of their "travel logistics, including flights, passports and visas." Kabir was to meet up with the three others and lead them to the Taliban, the court document said.

Santana and Deleon allegedly pre-trained on a firing range and at a paintball center and took the confidential source along with them.

Deleon told the confidential source he would quit school and withdraw his tuition money to help pay for the trip to Afghanistan, the criminal complaint said.

Santana told the confidential source said he would like to drive a truck bomb, if he could do it with a big truck. "Just drive it into like the baddest military base," he said, according to the document. "If I'm gonna do, I'm gonna do that. I'm gonna take out a whole base."