They call him "The Jihadist Next Door": an all-American high school student from Alabama who recently popped up in a remote corner of East Africa, where he is one of the key figures behind the Islamic insurgent group al-Shabaab's long and bloody guerrilla war against the government of Somalia.
Omar Hammami, who changed his name to Abu Mansour al-Amriki but is also known as "The American", is among 14 US citizens accused of crimes in a series of newly unsealed federal indictments of helping smuggle money, fighters and weapons to the terrorist organisation.
The suspects include 12 men who are currently believed to be fighting overseas and two women from the city of Rochester, southern Minnesota, who have been arrested for using a humanitarian charity as a "deadly pipeline" to provide support to the rebel army.
When they appeared in a packed courtroom in nearby St Paul on Thursday, both women entered not guilty pleas to charges they took donations supposed to help refugees fleeing the conflict and funnelled them to al-Shabaab. "We are not terrorists," said one of them, Amina Farah Ali.
The indictment filed against all 14 alleged co-conspirators by US Attorney General Eric Holder highlights the administration's growing concerns about the threat of home-grown Islamic terrorists, fuelled by last year's shootings at Fort Hood, along with the attempted bombing of Times Square in New York in May.
Until recently, the US public, along with most security experts, believed there was only a relatively slim chance that small-town America would contain radicalised youth inclined to commit to Jihad. But the widely publicised case of 26-year-old Hammami would suggest otherwise.
He was born to a Muslim immigrant father and a white Christian mother, and raised in middle-class respectability in the town of Daphne, Alabama, where he was a talented American Football player and boyfriend of a member of the high school cheerleading squad.
Hammami was popular, academically gifted and at the age of 15 was elected president of his class. But his life changed shortly afterwards: despite having attended the local Baptist church as a child – and although his small hometown does not even have a mosque – he decided to convert to Islam during his late teens.
At the University of Southern Alabama in Mobile, Hammami became president of the Muslim Students Association. His father, Shafik, an engineer with the State Highway department, says he disappeared shortly after finishing his studies there in 2002.
Speaking after the indictment was unsealed on Thursday, Attorney General Holder told reporters that Hammami has appeared in several propaganda videos for al-Shabaab and "has assumed an operational role in that organisation".
Hammami, for his part, has communicated via email with New York Times reporters about his role with the group. "We espouse the same creed and methodology [as] al-Qa'ida," he wrote in January. Asked if he considered America a legitimate target for attack, he responded: "It's quite obvious that I believe America is a target."
The investigation which led to this week's indictments and arrests began in October 2008, when it emerged that a US citizen from Minneapolis had carried out a suicide bombing in Somalia. Detectives found that around 20 young members of the local Muslim community had left for the country the previous year. Many of them were among the 14 indicted this week. Tracking those men down will be tricky; prosecuting Ali is made easier by the fact that she is in the US.
The document outlining specific charges against her claims that she sent funds to terrorist organisations through various "hawalas" – money-transfer businesses that are a common source of financial transactions in the Islamic world. Ali is accused of sending $8,608 (£5,400) to al-Shabaab on 12 occasions between September 2008 and July 2009.
The document also says that wiretap recordings reveal that after the FBI searched Ali's home in 2009, she contacted an al-Shabaab leader in southern Somalia and said: "I was questioned by the enemy here ... They took all my stuff and are investigating it ... Do not accept calls from anyone."