Unusually long fighting between organized criminal elements and the Mexican military that began early April 28 continued in several areas in and near the Choix, El Fuerte and Guasave municipalities of northern Sinaloa state. Narcomantas appeared May 7 in various areas of Sinaloa state, including Culiacan, Guasave and Los Mochis, accusing Sinaloa Federation leader Joaquin "El Chapo" Guzman Loera of colluding with the 89th Infantry Battalion, the military unit primarily operating in Choix. It has become clear that the military's primary adversaries in this conflict are the remnants of the Beltran Leyva Organization (BLO).

Why extended fighting erupted simultaneously in multiple locales remains unclear. On occasion, Mexico's criminal organizations intentionally engage authorities to divert attention from high-value targets, such as areas of drug production and high-level leaders' hideouts. However, these conflicts typically last no more than a day. The military's willingness to continue pursuing the gunmen into such remote mountainous terrain, which heavily favors the gunmen, also stands out. The conflict indicates that the dynamic between organized crime and the military in northern Sinaloa state may have undergone a significant change: The BLO, which has seen its operational capabilities diminish greatly since its split with the Sinaloa Federation, has now shown it can engage the Mexican military in a protracted conflict.

The death of the group's leader, Marcos Arturo Beltran Leyva, and the arrest of his successor and brother, Alfredo Beltran Leyva, greatly weakened the BLO. As it splintered into several groups, such as the Cartel Pacifico Sur, one of its larger successors, many of these new factions aligned with Los Zetas, which allowed them to survive in the mountains of northern Sinaloa with its lucrative concentration of marijuana and poppy fields and maintain their illicit drug production and distribution capability. 

According to Stratfor sources, some of the gunmen in Choix belonged to Los Zetas. While this has not been corroborated, the insurgent-style tactics and brazen standoff with the military fits with Zetas behavior in states like Coahuila and Tamaulipas, where engagements with the military are common. The continued existence of the BLO and its alliance with Los Zetas presents the Sinaloa Federation with a rival close to its home territory in the Sierra Madre Occidental and could obstruct Sinaloa's trafficking corridors northward toward the U.S.-Mexican border. Guzman thus stands to benefit from aggressive military operations in the mountains of northern Sinaloa.

Mexico Weekly Map May 9, 2012

The high value of the region's poppy cultivation, the possible existence of hideouts for high-value targets such as Hector Beltran Leyva, and the presence of several drug-trafficking organizations including Los Zetas mean the area is likely inundated with gunmen. As stated by the Military Region III commander, the military is deploying an additional 300 troops to the area in response to the conflict. There is no shortage of gunmen willing to defend the valuable territory, so continued pursuit of organized criminal elements in the mountains likely will lead to increased violence. 

May 1

• Gunmen killed three people sitting at an outdoor candy stand in Ciudad Juarez, Chihuahua state.
• Authorities discovered the body of a police officer in Tlaquepaque, Jalisco state, who was likely killed the previous day.

May 2

• Gunmen hiding in a motel in Estacion Bamoa, near Guasave, Sinaloa state, engaged a military convoy in a firefight that lasted two hours and left 15 gunmen and two soldiers dead.
• Five gunmen and one federal police officer died in Sain Alto, Zacatecas state, after a car chase.
• The Mexican navy arrested Luis Alberto "El Casanova" Perez Casanova in Xalapa, Veracruz state. Perez allegedly served as Los Zetas' security chief in Xalapa.

May 3

• Authorities found two photojournalists for local media outlet Notiver in black bags in a river in Boca del Rio, Veracruz state. The journalists were reported missing April 27.
• A newspaper vendor was shot dead on a street in Chihuahua, Chihuahua state.

May 4

• Nine individuals were hung from a bridge in Nuevo Laredo, Tamaulipas state. Along with the bodies, a narcomanta was displayed denouncing individuals coming to Nuevo Laredo "to heat up the plaza" and singling out Gulf cartel leaders such as Metro-4 and Juan Mejia "R1" Gonzalez.
• Authorities discovered 14 headless bodies stored in a van in front of the Association of Customs Agents building in Nuevo Laredo, Tamaulipas state, along with a narcomanta signed "El Chapo." The message demanded that the Mayor of Nuevo Laredo recognize the presence of the Sinaloa Federation in the city. The same day, authorities discovered 14 severed heads in three coolers in front of the city hall.
• Several gunfights in the Iztapalapa neighborhood of Mexico City left six dead and four wounded.
• Gunmen opened fire on a police patrol in San Nicolas de los Garza, Nuevo Leon state, killing one police officer and wounding another.

May 5

• A firefight between two groups left eight gunmen dead in Jerez de Garcia Salinas, Zacatecas state.
• At least two gunmen in a vehicle shot and killed a strip club bouncer in Monterrey, Nuevo Leon state, in front of the club.
• Gunmen traveling in a vehicle shot a man walking home in the Azcapotzalco neighborhood of Mexico City.
• Federal police detained alleged La Linea leader Javier "El Dientes de Ajo" Hernandez Marquez in Chihuahua state. According to authorities, Hernandez assumed the leadership of the group after the arrest of La Linea's previous leader 10 days before.

May 6

• Authorities discovered three dead men along a highway in Atoyac de Alvarez, Guerrero state.
• Federal police announced the arrest of 12 La Barredora members in Acapulco, Guerrero state.

May 7

• Authorities discovered the bodies of two executed men in the La Draga neighborhood of Mexico City.
• Gunmen shot and killed an individual inside his vehicle in Cajeme, Sonora state.
• Mexican authorities announced the arrest of Maria "La Tosca" Jimenez, the leader of a Los Zetas cell of sicarios (assassins), along with eight other people in Monterrey, Nuevo Leon state. Jimenez was arrested with three male sicarios the week before.