Twice as many Americans as previously reported by law enforcement have traveled overseas to join an al-Qaida-linked organization, a congressional investigation found.
The findings, discussed in a congressional hearing on Wednesday, are an indication the Somalia-based terrorist group has an even deeper reach into the U.S.
More than 40 Americans have traveled to war-torn Somalia to join the terrorist group al-Shabab, an investigation by Republican staff on the House Homeland Security Committee found.
Al-Shabab, which initially focused on regional grievances, has expanded its focus to include targeting the West and recruiting Americans toward that cause.
Counterterrorism officials fear the terror group with ties to al-Qaida is a growing threat to the U.S. In at least one instance, the government said, al-Shabab received terror training from al-Qaida's offshoot in Yemen.
Publicly, authorities have said at least 21 men left the Minneapolis area for Somalia since late 2007 and are believed to have joined the terror group. Four have died in the country, according to information from the FBI and family members who spoke to The Associated Press.
Others are feared dead, and the committee's investigation found that at least 15 of the 40 Americans have been killed while fighting. In recent years, more than 35 people from across the U.S. have been charged with connections to al-Shabab, including some who have been indicted for raising money to fund the terror group.
Details of the findings came out during the third in a series of congressional hearings examining the radical Islamic terror threat in the U.S.
The chairman of the committee, Rep. Peter King, R-N.Y., has been criticized for singling out one religion instead of looking at all issues of domestic extremism across the country. In response, King said only one group has killed 3,000 Americans: al-Qaida, a terrorist organization that espouses a violent interpretation of Islam.
The top Democrat on the committee said the threat from al-Shabab has been overstated, as the number of people who left the U.S. to go to Somalia is small and confined to a two-year period.
"Al-Shabab does not appear to present any danger to this homeland," Rep. Bennie Thompson, D-Miss., said.
Thompson's assessment is in direct contrast to that of some intelligence officials in the Obama administration.
Just Tuesday, the president's choice to lead the country's top terror analysis center told senators that the threat from al-Qaida affiliates around the world presents challenges.
"I'm especially concerned about the threat to the United States homeland from al-Qaida in the Arabian Peninsula _ AQAP, we call it _ as well as threats emanating from terrorist safe havens in Somalia and elsewhere," Matt Olsen said during his confirmation hearing Tuesday to be director of the National Counterterrorism Center.
Minnesota, home to the largest Somali community in America, has been the center of the federal investigation into the travels and recruitment of those who are believed to have joined al-Shabab, and these hearings have prompted some there to warn against generalizations about Somalis or Muslims. The mayor of Minneapolis and others issued statements touting the work of successful Somalis in Minnesota and noting their positive contributions to society, as business owners, students, religious leaders and elected officials.
Police Chief Thomas Smith of St. Paul, Minn., said his department has worked hard to build connections with the Somali community and hosts events like youth soccer games and other activities to build trust.
"Somali-American youth that may be tempted by an ideology of radicalization can now look to an expanded network of trust, including police officer mentors to provide support, resources and guidance to steer them in a positive direction," Smith told lawmakers Wednesday.
In 2007, a group of Minneapolis-area Somalis held secret meetings to plan trips to Somalia and created fake itineraries to fool family members, the government has said. Some went to malls and apartments, falsely telling members of the Somali community they were raising money to build a mosque or help relief efforts in Somalia, federal prosecutors have said. The money actually went to the travelers, who planned to join one group member's relative _ a senior member of al-Shabab in Somalia.
E.K. Wilson, FBI supervisory special agent overseeing the investigation in Minneapolis, said the bureau is only confirming two deaths of those who could be identified through DNA or fingerprints.
"We're aware of others that have been reported to be dead," Wilson told The AP. "We're monitoring that continually. But absent any remains or absent any sort of diplomatic notification, there's not really anything to confirm."
Experts said the threat of al-Shabab cannot be discounted just because the group has never carried out an attack against the U.S. They point to the Nigerian man, working for al-Qaida's Yemen branch, who tried to bring down an airliner over Detroit on Christmas 2009.
"The reality is we don't know what terrorist organizations are able to do looking forward. They are in some regards more aspirational than operational," W. Anders Folk, a former assistant U.S. attorney in Minnesota, told lawmakers Wednesday. "We don't know when they are going to cross the line from aspiration to operation."
Forliti reported from Minneapolis.