MINNEAPOLIS — Adnan Abdihamid Farah's parents took his passport away last year when it came in the mail, and his mother would later tell authorities she feared her son would "disappear."
She also stopped the 19-year-old from traveling with his brother, Mohamed Abdihamid Farah, when the siblings told her they were going to Chicago. Mohamed — who was older and given more freedom — made the trip and instead ended up in San Diego, where authorities say he was bound for Mexico and ultimately the Islamic State group in Syria.
"I cry all day," their mother, Ayan Farah, said Wednesday. "I don't know what happened."
The brothers are among six Minnesota men of Somali descent charged this week with terrorism-related offenses, accused of attempting to travel to Syria to join the Islamic State group. Family members have expressed shock to see the men caught up in a terror investigation, but people who track such cases say it's not uncommon for sibling relationships to play a role in recruiting.
Siblings Dzhokhar and Tamerlan Tsarnaev worked together to carry out the 2013 Boston Marathon bombing that killed three people and injured more than 260. Dzhokhar Tsarnaev's attorneys, trying to spare him the death penalty at trial, have argued that his older brother masterminded the attack and recruited Dzhokhar, the impressionable younger brother.
Two brothers linked to al-Qaida, Said and Cherif Kouachi, carried out the January attacks in Paris on the offices of the satirical newspaper Charlie Hebdo, killing 12 people.
William Braniff, executive director of the National Consortium for the Study of Terrorism and Responses to Terrorism (START), said an intimate relationship — like that of family members — is often the key that will lead someone with extremist views to action. He said it's hard to conspire with others over the phone or in emails or meetings without getting caught, but much easier to make plans with a sibling at home.
"The current security environment lends itself to that kind of tight-knit conspiracy," he said.
Authorities said another man charged with the Farah brothers, Guled Ali Omar, is the younger brother of Ahmed Ali Omar, who joined al-Shabab in 2007 and remains a fugitive. A court document says Guled Omar also had tried to go to Somalia in 2012 to join al-Shabab, and has made at least two attempts to travel to Syria in the last year.
U.S. Attorney Andy Luger described the group charged this week as friends and family members who recruited and inspired each other. He said the recruiting was "friend-to-friend, brother-to-brother."
Former prosecutor Anders Folk, who handled the initial al-Shabab cases in Minnesota, said younger siblings often look up to their older brothers or sisters.
"I don't think it provides any kind of excuse or diminishes at all their potential dangerousness or potential commitment to the cause, but it is certainly context for how people can get involved," Folk said, adding: "Who better to keep a secret than a sister or a brother?"
Ayan Farah said she thinks her sons were set up. Her reaction echoed that of some in the Somali community who suggested the role of an FBI informant in the case was entrapment.
She said her sons, two of seven children, still lived in the family home with her and her husband. Mohamed, 21, graduated from high school in 2012 and was studying at St. Paul Technical College with plans of becoming a science teacher. Adnan graduated from high school last year and planned to marry this summer, she said.
She said both are religious and frequently attended the mosque. They never strayed far from home, and liked basketball and soccer.
"The kids, they have a beautiful life," she said. "So I did not see anything for the problem."
She said Adnan told her he wanted to go to college in China, but she thought he was too young and she wanted him to stay in the U.S. She said she did not believe he wanted to join the Islamic State group.
"I keep the passport because Adnan, he's young. That's why," she said. "(I) say, 'Hey, you're not going anywhere.' ... And he listened."
According to an FBI affidavit, the mother took Adnan's passport because she "was fearful he would disappear and that they would 'not know where (he) went.'" The affidavit also says Adnan posted jihadist images on Facebook and last year told an informant, "There's nothing for me in this world, bro."
Ayan Farah said she saw her sons' activity on Facebook and nothing alarmed her.
The affidavit also says Mohamed was among four men who took a bus to New York City and were stopped at JFK Airport last November while trying to travel to Syria. During conversations recorded by the FBI informant, Mohamed allegedly said that he tricked his grandmother to get his passport.
On another occasion he said that "the American identity is dead."
"Even if I get caught, I'm whatever ... I'm through with America," Mohamed said, according to the affidavit. "Burn my ID."