The discovery of 14 bodies in an abandoned van outside the capital of San Luis Potosi, Mexico marks the fifth time that this number of corpses has been dumped in as many months, all of them apparently killed by the Sinaloa Cartel or its allies.

On August 9 Mexican police discovered 14 bodies left in a stolen vehicle at a gas station in San Luis Potosi, reported Vanguardia.

The state attorney said that the men were kidnapped in Coahuila, brought to Zacatecas, and then killed before being dumped in San Luis Potosi. The authorities have not released any information regarding the suspected perpetrators or messages left at the crime scene, but Proceso attributes the massacre to the Gulf Cartel and other groups allied against the Zetas.

Including the 14 bodies, at least 21 people were found dead in San Luis Potosi that day. A shootout between suspected gang members and the Federal Police and armed forces left three dead and several injured, forcing a nearby university to close down for several hours. Following the gun battle, state police also found four bodies bearing signs of torture.

InSight Crime Analysis

San Luis Potosi has not suffered the same high levels of violence as its neighbors to the north. The National Secretariat of Public Security recorded 224 reported homicides in the state during the first half of 2012, compared to 1,096 in Nuevo Leon and 730 in Tamaulipas. Recently, however, a turf battle between the Zetas and allies of the Sinaloa Cartel has caused an increase in bloodshed.

This most recent attack is at least the sixth time since April that authorities have discovered 14 bodies dumped together, leading Reuters to speculate that the number may be some kind of code for drug cartels. In April, 14 bodies were left in an abandoned truck outside the city hall in Nuevo Laredo, Tamaulipas. Then, in May, another 14 people were killed, their headless bodies left at the Nuevo Laredo Association of Customs Agents and their heads in coolers at Nuevo Laredo city hall. In June, 14 corpses were dumped in two seperate incidents in Mante, Tamaulipas, once on June 7 and again on June 23. Later that month, 14 dismembered bodies left in plastic bags were discovered in Veracruz.

All the killings were accompanied by notes saying that the dead were members of the Zetas, although authorities discovered no connection between the majority of the deceased and organized crime. The Sinaloa Cartel appeared to take credit for the first three massacres, while its ally the Jalisco Cartel New Generation (CJNG) was blamed for the fourth.