The war led some citizens to flee to Los Angeles, where El Salvadorans started MS-13, also known as Mara Salvatrucha or La Mara. MS-13 Gang Using Deportation To Expand Into South America, Europe ... The truce, signed in early March between the rival Mara Salvatrucha (MS-13) and Barrio 18 gangs (NotiCen, April 26, 2012), has by no means been a panacea for the impoverished country's debilitating crime epidemic.