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
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 was originally the enforcement wing of the
Zapata Espinoza was a commandante who 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 an estaca commandante in a pickup with three hit squad members and came upon the agents' vehicle about 2 p.m. 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."
Zapata Espinoza called for backup and forced the SUV into a median ditch. The hit men, armed with AK-47s, AR-15s and handguns, surrounded it. Zapata Espinoza opened the driver's side door and ordered the agents to get out. They refused. He fired three shots near the vehicle and walked to the passenger side. Avila attempted to explain in Spanish that they were
One of the agents slightly lowered a window, the statement said, and two hit men stuck a "long gun and a handgun" inside and started firing. Avila attempted to drive off, the vehicle stalled and the hit men continued to fire at the vehicle. Both agents were hit multiple times. The tires were shot out, the windows shattered and "there appeared to be a large amount of blood in the driver's seat."
Zapata Espinoza was arrested a week later by Mexican authorities in San Luis Potosi and extradited to the U.S. in December 2011. Last month, according to the statement of facts, he began talking to prosecutors about a plea deal. In that conversation, conducted in Spanish, "the defendant acknowledged his involvement in the attack" and agreed to plead guilty, the statement said.
According to court records unsealed Thursday, Ruben Dario Venegas Rivera, 25, and Jose Ismael Nava Villagran, 30, also pleaded guilty to being Zetas members and participating in the attack. Francisco Carbajal Flores, 38, pleaded guilty to assisting the Zetas after the ambush.