premise: MS-13 is a thing.
hypothesis: MS-13 ( Mara Salvatrucha ; also known as simply MS or Mara ) is an international criminal gang that originated in Los Angeles , California , US in the 1980s . The gang later spread to many parts of the continental United States , Canada , Mexico , and Central America , and is active in urban and suburban areas . In the U.S. , the MS-13 has an especially heavy presence in Los Angeles County and the San Francisco Bay Area in California ; the Washington , D.C. metropolitan areas of Fairfax County , Virginia , Montgomery County , Maryland , and Prince George 's County , Maryland ; Queens , New York ; Long Island , New York ; Newark , New Jersey , Plainfield , New Jersey ; Jersey City , New Jersey ; Elizabeth , New Jersey ; the Boston , Massachusetts area ; Charlotte , North Carolina ; and Houston , Texas . Members of MS are characterised by tattoos covering the body and also often the face , and by the use of their own sign language . Their wide-ranging activities have drawn the attention of the FBI and Immigration and Customs Enforcement , who have initiated wide-scale raids against known and suspected gang members , arresting hundreds across the country .