A Kenyan intelligence report reveals that a British woman played a major role in last month’s Nairobi mall massacre by Islamic militants, as Norway admits at least one of their citizens may also have been involved.

The reports illustrate the growing numbers of Westerners joining jihadist groups, particularly in Somalia and Syria, and underscore concerns that these individuals may soon return to conduct strikes on “soft targets” in Europe and the United States.

Sky News reports that Kenyan agents believe Samantha Lewthwaite — an ethnically-British convert to Islam — acted as “logistician” for an al-Shabaab terrorist cell in Kenya, apparently the same one that murdered 72 people at Nairobi’s Westgate Mall last month.

Dubbed the “White Widow” for her marriage to one of the suicide bombers that attacked London in 2007, she appears to be the right-hand woman to Ikrima, a Kenyan Muslim who was the target of last week’s failed Navy SEAL raid on al-Shabaab in southern Somalia.

Kenyan security forces raided the house where she was believed to be staying, but Lewthwaite managed to escape capture.

Also on Friday, Norwegian authorities said investigators had arrived in Somalia to determine whether one of their citizens may participated in the Westgate attack.

Norwegian police “received information that a Norwegian citizen of Somali origin may have been involved in the planning and execution of the attack, and… decided to initiate an investigation on this basis,” a spokesperson said.

Norway has a relatively large Somali expat community. Terror leader Ikrima briefly lived in Oslo and applied for asylum in 2008, but left before the process could be completed.

Experts worry about the recent surge of Western fighters, particularly Americans, who are traveling abroad to wage jihad in Somalia. A Wednesday hearing of the House Homeland Security Committee in Washington, D.C. focused on the sizable Somali community in Minneapolis, which since 2007 has sent around 50 fighters to al-Shabaab. At least seven of these Somali-Americans were later killed, including three in suicide operations.

Sheriff Richard Stanek, the chief law enforcement officer for Minneapolis and the surrounding area, told lawmakers that al-Shabaab recruitment efforts in his jurisdiction are widespread, sophisticated and difficult to control.

“I’d be less-than-candid if I didn’t tell you I was extremely concerned… about the potential for what they might bring in the future,” he said, adding that “we still have an uphill battle to stop recruitment and win over the Somali community at large.”

He explained that the closed nature and anti-Western sentiment of many in Minneapolis’ Somali community meant it was difficult to determine how many fighters had left for East Africa, whether they had returned to the United States and if they planned to continue waging jihad at home.

Stephanie Kostro, acting director of the counterterrorism program at the Center for Strategic and International Studies, told the panel that most Somali-Americans “seem to go [to Somalia] for nationalism and adventurism, not global jihad.” But she warned that could soon change.

Al-Shabaab has historically been a local uprising against the secular Somali government, but Kostro claimed that “in recent months, new leadership has consolidated around al-Qaeda-linked individuals” and assumed a more global focus. Last month’s assault on Nairobi’s Westgate Mall, she claimed, may be seen as a “coming-out attack” in this regard.

With the right motivation, Kostro argued that Somali-Americans could easily combine their geographical, cultural and linguistic knowledge of the United States with the training they received abroad to wreak havoc on American targets.

Follow Brendan on Twitter

Content created by The Daily Caller News Foundation is available without charge to any eligible news publisher that can provide a large audience. For licensing opportunities of our original content, please contact licensing@dailycallernewsfoundation.

All content created by the Daily Caller News Foundation, an independent and nonpartisan newswire service, is available without charge to any legitimate news publisher that can provide a large audience. All republished articles must include our logo, our reporter’s byline and their DCNF affiliation. For any questions about our guidelines or partnering with us, please contact licensing@dailycallernewsfoundation.org.