I first heard of the MS-13 "cliques" (stands for Mara Salvatrucha) from the Carrollton Police Academy. A Stratfor analysis reported that there are estimated between 8,000 to 10,000 hard-core MS-13 members now live in the US. The analysis studied the alleged links between MS-13 and al Qaeda and concluded that there are too many idealogical and practical differences between the two for them to really form a confederation.