That image seemed startlingly at odds with the Bangladesh native's arrest in an FBI sting this week on charges of trying to blow up the Federal Reserve Bank in New York with what he thought was a 1,000-pound car bomb.
"I can't imagine being more shocked about somebody doing something like this," said Jim Dow, a 54-year-old Army veteran who rode home from class with Nafis twice a week. "I didn't just meet this kid a couple of times. We talked quite a bit. ... And this doesn't seem to be in character."
Nafis' family in Dhaka, Bangladesh, denied he could have been involved in the plot. His parents said he was incapable of such actions and came to America only to study.
Federal investigators, often accused by defense attorneys of entrapping and leading would-be terrorists along, said the 21-year-old Nafis made the first move over the summer, reaching out for accomplices and eventually contacting a government informant, who then went to federal authorities.
They said he also selected his target, drove the van loaded with dummy explosives up to the door of the bank, and tried to set off the bomb from a hotel room using a cellphone he thought had been rigged as a detonator.
During the investigation, he and the informant corresponded via Facebook and other social media, talked on the phone and met in hotel rooms, according to a law enforcement official who was not authorized to speak publicly and spoke on condition of anonymity.
Nafis spoke of his admiration for Osama bin Laden, talked of writing an article about his plot for an al-Qaida-affiliated magazine, and said he would be willing to be a martyr but preferred to go home to his family after carrying out the attack, authorities said. And he also talked about wanting to kill President Barack Obama and bomb the New York Stock Exchange, a law enforcement official said.
Investigators said in court papers that he came to the U.S. bent on jihad and worked out the specifics of a plot when he arrived. While Nafis believed he had the blessing of al-Qaida and was acting on behalf of the terrorist group, he has no known ties, according to federal officials.
Nafis, who at the time of his arrest Wednesday was working as a busboy at a restaurant in Manhattan, was jailed without bail. His attorney has not commented on the case, but in other instances where undercover agents and sting operations were used, lawyers have argued entrapment.
Investigators would not say exactly how he initially contacted the government informant.
Police Commissioner Raymond Kelly, whose department had a role in the arrest as a member of a joint federal-state terrorism task force, said the entrapment argument rarely prevails.
"You have to be otherwise not disposed to do a crime," Kelly said. "And if it's your intent to do a crime, and somehow there are means made available, then generally speaking, the entrapment defense does not succeed."
Nafis was a terrible student in his native Bangladesh, and his middle-class parents said he persuaded them to send him to study in the U.S. as a way of improving his job prospects. They don't believe he was planning an attack.
His father, a banker, said Nafis was so timid he couldn't venture out onto the roof alone.
"My son couldn't have done it," Quazi Ahsanullah said, weeping.
"He is very gentle and devoted to his studies," he said, pointing to Nafis' time studying at the private North South University in Dhaka.
Belal Ahmed, a spokesman for the university, said Nafis was put on probation and threatened with expulsion if he didn't bring his grades up. Nafis eventually stopped coming to school, Ahmed said.
Ahsanullah said his son had argued that a U.S. degree would give him a better chance at success in Bangladesh. "I spent all my savings to send him to America," the father said.
Nafis moved to Missouri, where he studied cybersecurity at Southeast Missouri State University. He also became vice president of the school's Muslim Student Association and began attending a mosque.
But he withdrew after one semester and requested over the summer that his records be transferred to a school in Brooklyn. The university declined to identify which school.
Dow, his former classmate at Southeast Missouri State, said Nafis spoke admiringly of bin Laden. At the same time, "he told me he didn't really believe bin Laden was involved in the twin towers because he said bin Laden was a religious man, and a religious man wouldn't have done something like that," Dow said.
He said Nafis gave Dow a copy of the Quran and asked him to read it. But he "didn't rant or rave or say crazy stuff," Dow said.
"What really shocked me the most was he had specifically spoken to me about true Muslims not believing in violence," Dow said.
Dion Duncan of St. Louis, a fellow student and member of the Muslim organization, said: "Nafis was a good kid. He showed no traces of anti-Americanism, or death to America, or anything like that. He was a trustworthy, honest kid."
"He was polite and courteous. He was helpful. All the things you would expect from a good Muslim kid. He prayed five times a day," Duncan said.
Associated Press Writers David B. Caruso in New York, Jim Suhr in St. Louis, and Farid Hossain in Dhaka, Bangladesh, contributed to this report.
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