NEW YORK - Officially, the FBI agents who swarmed Donald Ray Morgan at Kennedy Airport this month were there to arrest him on a mundane gun charge. But they whisked him away to their Manhattan office and grilled him for two hours on an entirely different topic: Islamic State extremists.
Over and over, they asked Morgan, a 44-year-old North Carolina man, converted Muslim and author of pro-extremist tweets, whether he had traveled to Syria to support the militant group. More important, they wanted know whether he could identify any fighters with U.S. ties who had left the region to return to America.
The questioning, recounted in a recent court hearing, offered a glimpse into U.S. law enforcement's intensifying efforts to identify Islamic State sympathizers who could help export the group's brand of violent jihad to the United States.
They come amid a new barrage of U.S. airstrikes against the Islamic State group that beheaded American journalist James Foley. The group called Foley's killing revenge for previous strikes against militants in Iraq.
Federal and New York Police Department officials have estimated that at least 100 Americans could be fighting with the Sunni extremists who have seized territory in northern and western Iraq. In April, a Colorado woman and convert to Islam was arrested before she could travel to Syria to marry a fighter she had met online. More recently, a Texas man who was arrested trying to board a flight to Turkey pleaded guilty to terror charges alleging he wanted to join the group.
In a Pentagon news conference, Joint Chiefs Chairman Gen. Martin Dempsey called the Islamic State an "immediate threat," in part because of the number of Europeans and other foreigners who have traveled to the region to join the group.
"And those folks can go home at some point," he said.
An FBI and Homeland Security Department intelligence bulletin issued Friday said there were no credible or specific threats from the Islamic State against the U.S. homeland. However, it cautioned that "violent extremists who support (the group) have demonstrated the capability to attempt attacks on U.S. targets overseas with little-to-no warning."
NYPD counterterrorism officials, long wary of another al-Qaida strike since the Sept. 11 attacks, have increasingly turned their attention to the Islamic State threat and efforts to recruit supporters through social media.
The group used hashtags like #BewareAmerica and #CalamityWillBefallUS to make threats against the United States, NYPD analyst Rebecca Weiner said at a recent briefing for private security officials.
"What we've seen in these hashtag campaigns is a lot of pictures of U.S. cities, including New York," she said.
Weiner cited the arrest this year of a Frenchman - radicalized after spending a year in Syria - in a fatal shooting of three people at the Brussels Jewish Museum. An AK-47 found in his possession was wrapped in a flag with inscriptions from the Islamic State - giving more cause for concern about "about returning foreign fighters from Iraq and Syria," she said.
Morgan, who once worked as a reserve police officer in North Carolina, spent eight months before his arrest in Lebanon, where his wife lives. He caught the attention of federal authorities in July with his Twitter rants under the name "Abu Omar al Amreeki." In one, he pledged allegiance to Islamic State leader Abu Baker al-Baghdadi. Another asked Allah for martyrdom.
Others read, "To the brothers inside Syria and Iraq, be humble and grateful. Many of us are trying to come. Some are arrested and others are delayed," and "Honestly, can we not kill one piece of crap Zionist?"
At the time, Morgan, of Landis, North Carolina, was wanted for selling an assault rifle and other weapons over the Internet - a business he continued when he was overseas with the help of his ex-wife. U.S. authorities used the gun warrant to intercept him at Kennedy Airport on Aug. 2 and question him about the Islamic State, FBI agent J.L. Pickford testified at a bail hearing Aug. 5.
Morgan admitted that he was the "Amreeki" on Twitter and that, as a devout Muslim, he was required to support any caliphate imposing strict Sharia law, the agent said. But he denied knowing the identity of any extremists who may be moving back and forth between war zone and the United States.
"I take it that was the $64 million question and he said he didn't have a clue," said federal defender Peter Kirchheimer.
Despite the agent's admission that there was no direct evidence Morgan ever joined or provided material support to the Islamic State - designated by U.S. officials as a terrorist organization - prosecutors argued he had the potential to supply arms to the militants. A judge ordered him held without bail and sent him to North Carolina to face the gun charge.
Morgan's lawyer in North Carolina, Richard McCoppin, said he won't discuss any pending case. Reached by phone, Morgan's ex-wife also declined to comment.
Jibril Hough, spokesman for the Islamic Center of Charlotte, said he didn't recognize Morgan. Hough said he could see how someone can get frustrated with U.S. foreign policy, but not enough to turn on their beliefs.
"Anyone who would be willing to join a group like that is leaving the principles of their faith if they call themselves a Muslim," he said.