FBI agents took Nayef Qashou into custody Monday. He's charged with lying to the FBI and destroying records.
In a newly unsealed affidavit, the FBI says Qashou arrived in the U.S. through Atlanta's airport in 2015, planning to study nursing at an Opelika, Alabama, community college. The FBI interviewed him more than a dozen times over the next four years.
He used encrypted phone apps to communicate with suspected terrorists who told him he should carry out an attack in the United States, the FBI said.
"Qashou would not tell interviewers exactly how he responded to the suggestion to conduct a U.S. attack," FBI Special Agent Scott Sullivan wrote in the sworn affidavit. "He stated he essentially responded by saying the only way he could justify an attack is for it to be against U.S. Armed Forces personnel on U.S. soil."
The nature of the encrypted communication was to discuss attacks against U.S. forces, among other things, the affidavit states. FBI agents searched his home in Auburn, telling a judge they were looking for computer equipment and computer storage devices.
Qashou also told FBI agents he does not believe in violence, but would help the Islamic State and would "drive fuel trucks, feed troops, and use a gun to defend against U.S.-led attacks against ISIS," the affidavit states.
Qashou consented to numerous interviews at the FBI's Auburn field office, where he voluntarily shared some information - such as his desire to join fighters in Syria, Sullivan wrote in the affidavit. But he also tried to minimize his support of "radical Islamic ideology," the affidavit states.
"Qashou stated he believed ISIS is fighting a humanitarian war that will benefit all Muslims in the Middle East," it states.
The aim of one interview was to "establish a baseline of Qashou's beliefs in order to determine which Islamic groups he was willing to join if he traveled to Syria and to determine what he is willing to do as a supporter for ISIS if his travels were successful," according to the affidavit.
He ended one of the interviews by saying he felt "it was his duty as a Muslim to inform the interviewing agents that he thinks the Boston Marathon bomber, Dzhokhar Tsarnaev, is innocent and the FBI should reopen the case to examine all the evidence."
Qashou is a dual Jordanian and United States citizen who grew up in Saudi Arabia, authorities said.
Court records don't list an attorney who could be reached on Qashou's behalf. He is being held in a detention facility in Montgomery.
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