WASHINGTON - A Mexican drug cartel commander pleaded guilty Thursday to murder and attempted murder in a 2011 ambush south of the border that left one American agent dead and a second injured, and which sharply strained U.S.-Mexico relations.
The commander, Julian Zapata Espinoza, 32, also known as Piolin, joined three other defendants who had previously pleaded guilty to various charges related to the shooting.
The developments in federal District Court in Washington also provided new details about the attack.
U.S. Immigration and Customs Enforcement Special Agents Jaime Zapata and Victor Avila were traveling near San Luis Potosi, Mexico, when a convoy forced them off the road. Two armed groups surrounded their vehicle and demanded they step out, in an attempt to steal the agents' armored SUV.
When the agents refused and identified themselves as American diplomats from the embassy in Mexico City, the assailants - later identified as members of the Zetas cartel - "fired weapons near and into the vehicle, striking both agents," court records show. The cartel members "continued to fire at the vehicle as the agents attempted to escape by driving away."
Zapata died at the scene. Avila was seriously injured.
Zapata Espinoza was described in the records as a hit squad commander for the Zetas, a heavily armed Mexican narco-trafficking cartel with deep drug and smuggling routes into the United States. Zapata Espinoza, like the other three defendants, faces life in U.S. prison with no parole.
Ronald C. Machen Jr., the U.S. attorney in Washington, said there were still others believed hiding in Mexico who were wanted as well.
"Our work in this critical case will continue until all of those who participated are held accountable," he said.
According to a "stipulated statement of facts" signed Thursday by Zapata Espinoza and prosecutors, the Zetas were originally the enforcement wing of the Gulf cartel but in recent years split into their own trafficking organization. Made up mostly of Mexican special forces deserters, the gang has morphed into one of the most violent and sophisticated cartels, with a hierarchy that mirrors the military and hit squads called estacas.
Zapata Espinoza, as a commander, controlled a stretch of Highway 57 between San Luis Potosi and Santa Maria del Rio.
On Feb. 15, 2011, the statement said, Zapata Espinoza was on duty as a hit-squad chief in a pickup with three members when they came upon the agents' vehicle. They noticed the SUV was armored and "decided to steal it for use by the Zetas." They also wanted to check whether the vehicle was carrying rival cartel members the Zetas thought "should be neutralized."