|1960s||The 18th Street Gang is formed in the Pico Union district of Los Angeles. Sometime later, Mara Salvatrucha (MS-13) is formed, possibly as a splinter group. The two gangs become rivals.|
|1980||Civil war begins in El Salvador, lasting 12 years and claiming an estimated 75,000 lives. Honduras and Guatemala suffer similar bloody wars throughout this period.|
|1980s||Central Americans flee the violence in their home countries for U.S. ghettos, finding themselves without work and needing protection from the local Mexican gangs that despise and threaten them. Ranks of the maras (gangs) swell in the U.S.|
|1992||Peace accords end the Salvadoran civil war. Over the next several years the U.S. will begin to deport Salvadoran gang members to their home country in large numbers. The gangs grow to play a large role in the drug trade in the U.S., and develop a reputation for brutal violence.|
|1996||The U.S. passes the Illegal Immigration Reform and Immigrant Responsibility Act of 1996 on September 30. A broad piece of legislation aimed at reducing illegal immigration, the Act rapidly increases the pace of deportation of gang members.|
|1997||The son of Honduran President Ricardo Maduro is kidnapped and murdered by gang members. The Honduran government announces a zero-tolerance policy on gangs.|
|1998||According to statistics from the Department of Homeland Security, more than 34,000 criminals are deported over the next seven years to El Salvador, Guatemala, and Honduras.|
|2003||A study by the United Nations Development Programme (UNDP) estimates the cost of violence to El Salvador in 2003 at $1.7 billion: 11.5% of its GDP.|
|2004||Murder rates are 46 per 100,000 people in Honduras; 41 in El Salvador, and 35 in Guatemala. In contrast, the the U.S. murder rate is 5.7 per 100,000.|
In Honduras, MS-13 members attack a public bus with automatic weapons, killing 28 people.
|2005||In the U.S., Operation Community Shield arrests 103 gang members in February and March, and another 582 in August.|
In Honduras, a brief truce between the gangs ends when some 35 members of Mara 18 are killed by MS-13 members in a coordinated attack across several prisons.
|2006||Statistics from the U.S. National Drug Intelligence Center estimate up to 10,000 active MS-13 members in up to 30 U.S. states.|
Some 25,000 gang members are estimated to be active in El Salvador, which averages 10 homicides per day, and suffers from prisons which operate at double capacity.
|Sources: U.S. Citizenship and Immigration Services; CIA World Factbook; NEWSHOUR WITH JIM LEHRER; THE BOSTON GLOBE; THE VANCOUVER PROVINCE; THE ECONOMIST.|