Sadiyo Omar had no idea where her son had gone until the sobbing 20-year-old phoned her from Turkey on Saturday.

"Why, why are you there?" she asked.

Her son, Abdi Mohamed Nur, a graduate of Southwest High School in Minneapolis, gave no explanation. When she begged him to come home, she said, he cried some more.

Kyle Loven, spokesman for the FBI in Minneapolis, declined to discuss Nur on Wednesday but said the agency has growing concerns that Somali-Americans from Minneapolis are traveling to Syria to fight the regime of President Bashar Assad.

"We believe that persons who have traveled overseas are traveling primarily to Turkey and once they are entering Turkey, they are crossing unfettered into Syria through the common border," Loven said.

Interviewed in her south Minneapolis apartment on Wednesday, Nur's mother appeared distraught. Omar said her family had called the FBI in hopes the authorities could help locate her son. "I want to find the people who told him to go to Turkey," she said.

Nur's sister told the Voice of America radio network this week that the FBI made some inquiries and told her that Nur was indeed in Turkey, where officials suspect he went in order to join the civil war in Syria.

A refugee family

Omar said that she and her son were born in Somalia and lived in a Kenyan refugee camp before the family came to the United States in 1980. She is now a U.S. citizen, as is her son.

She said her son graduated from Southwest High last June, which the Minneapolis School District confirmed. She said he was a "good student" and got A's in math.

He also attended Normandale Community College in Bloomington and had said he wanted to become a lawyer. "He's smart," Omar said, speaking in Somali as a friend acted as an interpreter.

Nur shared Omar's small apartment, and she said he was a responsible son, washing clothes and scrubbing the floors.

Nur left Minneapolis last Thursday at 5 p.m., she said, and at 6:40 p.m. his cellphone went dead. She kept trying to call him.

Omar said she then learned that Nur, with the help of a friend, had applied for a passport. Worried, the family called the FBI.

His sister told a reporter from Voice of America, the U.S.-sponsored radio network, that Nur had switched from one mosque to another recently and had begun to change over the past months. He sent a text to his sister last week, the day before he left for Turkey, saying he was going to join the jihad and told her not to worry, according to the radio report.

She declined to be interviewed for this article.

It is a violation of federal law for U.S. citizens not associated with the American military to participate in armed conflicts in foreign countries. In addition, the FBI is worried that Minneapolis Somali-Americans are joining organizations designated by the U.S. State Department as terrorist groups, which is also a federal crime.

Loven said the FBI did not have details on what groups young men coming to Syria from Minneapolis might be joining.

"These [terrorist] organizations are ever changing their names and changing alliances. They operate under the umbrella of the opposition," Loven said, "but these factions don't work in unison with each other."

The local FBI office is continuing to talk to Somali community leaders and activists, asking them to notify the agency if they know of anyone who is considering going to Syria.

"One of the primary focuses is to prevent young people from traveling to Syria to fight," Loven said. "This is the priority."

FBI agents met with community leaders on Tuesday at the Brian Coyle Community Center. One of the FBI agents present was Jane Rhodes-Wolfe, acting special agent in charge of the Minneapolis office. She has been involved in liaison efforts with the Somali community, Loven said.

The FBI is trying to prevent a repeat of events in 2007, when a group of young Somali-American men from Minneapolis went to Somalia to fight Ethiopian troops there.

Some of them joined Al-Shabab, which was the principal insurgent group opposing Ethiopian troops. The State Department concluded that Al-Shabab had ties to Al-Qaida and designated it a terrorist group.

Some Somali-Americans from Minnesota were prosecuted and convicted of joining the group, raising funds or paying for people fly to Somalia to fight. The bulk of the federal trials concluded in Minneapolis last year, some ending in long prison sentences for the defendants.

Loven said the FBI is trying to determine what recruitment efforts are drawing local young people to go to Syria. He said one method, which is difficult for law enforcement to investigate, is the use of videos produced by jihadist websites overseas.

Nur's mother said Wednesday that she had no idea that her son's ideas had changed so dramatically and that he was planning to go to Syria.

"Every mother has to keep looking after their sons to keep this from happening," she said. "I love him. I want to see him grow up."

Staff writer Steve Brandt contributed to this report.

Randy Furst • 612-673-4224