How many they've recruited is uncertain and unsettling.
That at least two Americans of Somali descent may be among the attackers in the Nairobi Mall massacre is sending chills through the U.S. Intelligence Community and through One Police Plaza in New York.
"There is a steady flow of young men for the most part wanting to go to Somalia and the fact that they can be trained and come back here and be used as a weapon is of great concern," NYPD Commissioner Ray Kelly said.
Commissioner Kelly is so concerned that he has sent a team to Nairobi to learn everything they can about the attack.
"We're trying to figure out how the bad guys are upping their games and what they've learned from the last attacks and what new techniques they bring to bear," said Samuel Rascoff, former NYPD Intelligence.
Of particular interest to the NYPD, is whether Americans were involved and if so when did they leave the states. They want to know if they part of the 15 to 40 young men from Somali communities in Minnesota and Ohio believed to have been recruited by Al-Shabab. They also want to find out if the mall attack suggests a shift from transportation targeted strikes to even softer targets.
"And suggests a small number of guys armed to the hilt can do massive violence if they start shooting up malls or hotels; these are nightmare scenarios for a police commissioner in NY," Rascoff said.
The question remains, does this al Qaeda off-shoot have the ability to strike on U.S. soil?
"So is it impossible? No. Is it certainly less likely than overseas, yes, I believe it is," Kelly said.
Commissioner Kelly has repeatedly said that the threat to New York since 9/11 is not from abroad, but from within.
And that was the case with the Boston Marathon bombing in which the Tsarnaev brothers became self-radicalized.
The fear is that American youth who join the cause of the militant Al-Shabad in Africa will come back home radicalized and trained in terrorism.
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