Mexican drug cartel member Julian Zapata Espinoza pleaded guilty Thursday to the killing and wounding of two U.S. federal agents in Mexico.
The guilty pleas of three other men were unsealed in connection to the shooting.
Zapata Espinoza pleaded guilty in a courtroom here to murder and attempted murder of an officer or employee of the U.S. in the Feb. 15, 2011, shootings of the U.S. Immigration and Customs Enforcement agents.
The unsealed pleas show that Jose Ismael Nava Villagran pleaded guilty to those charges in 2012, as did Ruben Dario Venegas Rivera in 2011.
All three admitted to being members of a Los Zetas Cartel hit squad and to directly participating in the attack, which resulted in the death of ICE agent Jaime Zapata and the wounding of his colleague Victor Avila. Both agents were based in Texas.
A fourth defendant, Francisco Carbajal Flores, pleaded guilty in 2012 to being an accessory after the fact to the murder and attempted murder, along with conspiracy to participate in a racketeering enterprise, his unsealed plea shows. He admitted helping Zetas members after the attack.
All four men face up to life in prison.
According to court documents, Zapata Espinoza, a commander in Los Zetas Cartel, tried to hijack the agents' armored government vehicle as it was driving on Highway 57 in San Luis Potosi. After hit squads forced the vehicle off the road and surrounded it, Zapata Espinoza ordered them to get out. The agents refused and tried to identify themselves, in Spanish, as U.S. diplomats from the American embassy, but the hit squad members fired into the vehicle, striking both agents.
Several family members of the victims were in the courtroom for Zapata Espinoza's plea, including Jaime Zapata's parents.
Zapata Espinoza is known by the nickname "El Piolin," or Tweety Bird, apparently because of his short stature.
U.S. District Court Judge Royce Lamberth said the U.S. agreed not to seek the death penalty in exchange for Mexico's extradition of Zapata Espinoza. The Mexican army has said Zapata Espinoza mistakenly believed Jaime Zapata was part of a rival gang.
In a statement, Acting Assistant Attorney General Mythili Raman called the agents "American heroes who dedicated themselves to protecting the United States, only to be attacked by vicious thugs."
Based on reporting by The Associated Press.