Massive, running gunbattles broke out between suspected drug traffickers on the streets of this violent border city Saturday, killing 13 people and wounding nine, law enforcement officials said. All of the dead were believed to be drug traffickers, possibly rival members of the same cartel who were trying to settle scores, said Rommel Moreno, the attorney general of Baja California state, where Tijuana is located. Eight suspects and one federal police officer were injured, none gravely, said Agustin Perez Aguilar, a spokesman for the state public safety department. The suspects are being held on suspicion of weapons possession among other possible charges. Police recovered 21 vehicles, many with bullet holes or US license plates, and a total of 54 guns at various points in the city where the battles broke out in the pre-dawn hours, Perez Aguilar said.