Mara Salvatruchas (MS or MS-13) is a violent criminal group founded by El Salvadoran immigrants in Los Angeles in 1980. For most of its history the group has functioned like a street gang -- engaging in deadly spats with rival gangs, participating in petty crime and narcotics dealing, and maintaining local turf both in major cities and in prisons. The gang's original purpose was to protect El Salvadorans from other Los Angeles gangs. Though its roots may be in the Salvadoran community, Mara Salvatruchas has expanded to include members from other Central American countries. In addition to changing its composition, the gang may also be expanding its tactics. Some of its more recent actions fit the profile of terrorism rather than traditional gang activity.  <P><br /><br />MS differs from most gangs in its vast size and international presence. Estimates vary, but most sources agree that there are more than 50,000 members of Mara Salvatruchas worldwide -- perhaps many more. Furthermore, Mara members are found in large groups from the streets of American cities to the countryside of Central America to the jails and prisons of both. The group's large prison presence allows it to use incarceration to improve organization and recruitment. Compounding matters, many MS members detained in the United States are deported rather than imprisoned, a process which feeds the gang population in Central America. <P>  <br /><br />The expanded MS presence in Central America has led to significant new violence in countries trying to recover from legacies of political conflict. Honduras, El Salvador, and Guatemala have murder rates many times that of the U.S., and some estimates suggest that Mara Salvatruchas and its arch-rival, MS-18, are responsible for as much as half of the violent crime in those countries. One incident in December 2004 had all the components of a terrorist attack: MS members stopped a bus and opened fire with automatic weapons, killing 28 people and wounding many more. The attackers left a note claiming the incident in the name of the Cinchoneros Popular Liberation Movement, a former terrorist group that has not been active since 1991. The Honduran government blames MS. The random attack may have been a threat to a rival gang or an attack designed to discredit the government's anti-gang efforts. <br />