MEXICO CITY (AP) - Gunbattles between rival drug gangs in the Mexican border city of Reynosa have left 12 people dead, authorities say.
The security spokesman for the northern state of Tamaulipas said five people were killed in two gunbattles Thursday. Another seven people were killed earlier in the violence that began Tuesday.
The disputes between rival factions of the Gulf cartel follow the killing of leader Julian Loisa Salinas, known as "Comandante Toro," by military personnel in late April.
The cartel gunmen have burned vehicles, blocked roads, attacked military patrols and fought gunbattles on city streets.
The administration of President Enrique Pena Nieto has long faced security problems in Tamauilpas, as in many other border areas, but in the last year violence has spread to other parts of Mexico that had previously been relatively peaceful.
On Wednesday, gunmen believed to be linked to fuel-theft gangs opened fire on military patrols, killing four soldiers. The ensuing confrontation left six assailants dead.
The gunmen used local residents as human shields to attack the army, and townspeople blocked roads to demand the army be withdrawn.
On Friday, during a speech commemorating the Cinco de Mayo festivities, Pena Nieto acknowledged that the thieves, who drill into government pipelines to steal fuel, have recruited local residents in some parts of Mexico.
"The organized crime groups use, and deceive, the people to commit crimes," Pena Nieto said. He called on prosecutors and the state-owned oil company to come up with a strategy to combat pipeline thefts.
The Pemex oil company has announced plans to step up security in the past, but has apparently failed to implement them. The company no longer even releases figures on the number of illegal pipeline taps, but 5,574 were found in 2015 alone.
In a separate incident involving drug traffickers, Mexican federal police announced Friday they caught four suspects who allegedly used hidden compartments on buses and trucks to smuggle narcotics to the United States.
The suspects were caught on Mexico City's outskirts with about 400 pounds (185 kilograms) of cocaine and 13 pounds (5.8 kilograms) of heroin.