MEXICO CITY -- At least 15 people were killed in brazen shootouts over the weekend in the large coastal city of Tampico, in a border state that had been experiencing a relative lull in organized-crime-related violence.
Mayor Gustavo Torres said Monday that the gun battles began Saturday night and lasted, sporadically, until Sunday night. He said the gunmen and victims were from the Gulf cartel, a drug-trafficking network that dominates part of Tamaulipas state.
Many in Tamaulipas said they feared a return to the recent past, when the Gulf cartel, backed by members of the larger Sinaloa faction from the Pacific Coast, waged vicious, near-daily fights with the Zetas, a paramilitary force that had broken off from the Gulf cartel.
Eventually, the Zetas and the weakened Gulf group apparently divvied up the state and violence subsided slightly. Nonetheless, migrants passing through continued to be preyed upon by criminal gangs.
"We thought these things [gun battles] were a thing of the past," Torres told a radio interviewer.
A handful of schools in Tamaulipas, including a university branch, suspended classes because of the violence.
Tampico is on the border of Tamaulipas state, which abuts Texas, and coastal Veracruz state, along a much-used route for smuggling people and drugs. People familiar with the area say the weekend's violence probably had more to do with disputes within the Gulf cartel over control of non-drug enterprises, such as human-trafficking operations and theft of oil supplies.
After several arrests or killings of top leaders, the cartel has reportedly disintegrated into numerous factions, such as the Alligators.
Torres described the latest bloodshed as a "settling of scores" among traffickers.
The names of the dead, at least two of whom were women, were not released.
Last week, military authorities arrested a Gulf lieutenant in the Tamaulipas city of Reynosa, captured along with weapons and communications equipment. His presumed supporters reacted by blocking city streets and opening fire on police, killing at least one.