This been going on since 2006, but continues to cause great unrest in Mexico due to the extensive fighting between cartels or between cartels and security forces. According to an analysis by Scott Steward in 2017, last year's homicide rates were 10 percent higher than in 2015.
The situation no longer involves a handful of large groups, but a number of smaller, regionally-based networks. This is called Balkanization. This has increased flashpoints and murder rates in many Mexican cities.
Three core areas of operation include Tamaulipas, Tierra Caliente, and Sinaloa.
Tierra Caliente (Southern Mexico):
The Cartel de Jalisco Nueva Generacion (CJNG) became one of the most powerful organizations and now clashes with the Sinaloa Federation and the Los Zetas
Tamaulipas (north and east):
Cartels here have been in conflict since 2010, when Los Zetas declared war on their former masters. After the arrest of its leaders, it split into the Cartel del Noreste and Vieja Escuela Zetas ("Old School Zetas"). Both groups have been a brutal fight for Nuevo Laredo and Ciudad Victoria for the past two years, with mutilations and beheadings being common.
The leader of the Sinaloa Federation, Joaquin “El Chapo” Guzman, who broke out of prison in 2005, was extradited to the U.S. on January 19 this year. The information he may provide to the U.S. could have a big impact. The region's smaller crime groups continue operating in the "golden triangle," a remote area that is difficult to police and is good for growing opium and marijuana.