International

I did not know that the largest community of Somali immigrants in the United States is in Minnesota. From Mail Online:

For years Minnesota has been the center of a federal investigation into the recruiting of fighters for al-Shabab. Authorities say about two dozen young men have left Minnesota since 2007 to join the group. Minnesota's Somali community is the largest in the U.S.

The al-Shabab terrorists in Kenya apparently had an international flavor, recruiting from all over the world for this evil undertaking.

Likewise, the victims of the terrorist murderers were from all over the world.