Fourteen assassinations attributed to narco gangs were carried out May 20 in Mexico City, Chihuahua, Nuevo León, Guerrero, Sinaloa and Oaxaca. Additionally, federal army troops exchanged fire with 20 gunmen with AR-15 automatic rifles, bullet-proof vests and uniforms of the Federal Agency of Investigation (AFI) at a checkpoint on the Apatzingán-El Alcalde road in Michoacán.

On May 19, three police officers were gunned down around the northern industrial city of Monterrey. Commander Fidel Reyna and agent Rene Reyes of the Santa Catarina municipal police force were ambushed with a spray of automatic rifle fire as they drove their patrol car through the Monterrey suburb.

One person was killed when gunmen attacked a Prosecutor General of the Republic (PGR) office building in Santa Cruz Huatulco, Oaxaca. An AFI agent was also gunned down outside Oaxaca City May 18.

In Sonora, the state Prosecutor General announced that the group of gunmen responsible for the May 16 attack at Cananea that left five police dead was made up for former army personnel. (El Universal, La Jornada, May 21)

Federal army and police troops "sealed" the state border of Chiapas and Tabasco May 18 to prevent the escape of assassins who killed Raúl López, a high-level investigator for the Tabasco state Prosecutor General. (APRO, May 18)

In the midst of the escalating violence, Amerigo Incalcaterra, representative of the UN High Commissioner for Human Rights, protested the use of Mexico's armed forces in anti-drug efforts. "We counsel against the use of the army in tasks of public security," he told reporters, citing the risk of human rights violations. (La Jornada, May 18)

See our last post on Mexico and the drug war, Oaxaca, Michoacán and Tabasco.