Mexico drug cartel commander pleads guilty in murder of U.S. official

NEW YORK (Reuters) - A Mexican drug cartel commander known as "Tweety Bird" pleaded guilty on Thursday in federal court in Washington to ordering the ambush and murder of U.S. immigration agents in 2011, according to U.S. officials.

The plea related to a February 2011 incident when two "hit squads" from the Los Zetas drug cartel forced an armored U.S. government vehicle off a highway near Mexico City and surrounded it, federal prosecutors said.

Zetas commander Julian Zapata Espinoza, known as "El Piolin" (Tweety Bird), ordered U.S. Immigration and Customs Enforcement special agents Jaime Zapata and Victor Avila out of the car, said Acting Assistant Attorney General Mythili Raman of the U.S. Justice Department's Criminal Division.

When the agents refused, identifying themselves as American diplomats from the U.S. embassy, Espinoza ordered the gunmen to fire on the vehicle. Zapata was killed and Avila was seriously wounded but survived, officials said.

Espinoza pleaded guilty to the murder of Zapata and the attempted murder of Avila. He had been extradited from Mexico to the United States in December 2011, and indicted by a grand jury in April 2012.

The court on Thursday unsealed three earlier guilty pleas related to the attack. Two other men admitted to being Zetas cartel members and participating in the attack, and a third admitted to assisting the Zetas in the deadly ambush.

All four men face a maximum sentence of life in prison. No sentencing date has been set yet.

U.S. officials have traditionally responded with relentless pressure on Mexican drug gangs who target American law enforcement officials.

When U.S. Drug Enforcement Agent Enrique "Kiki" Camerena was abducted and killed in 1985 by the Zetas gang members, U.S. officials "virtually shut down the border ... and began car to car searches, ostensibly for Camerena," said Nathan Jones, a drug policy analyst at Rice University's James Baker School of Public Policy.

"What they were really doing was establishing a deterrent, drawing a line in the sand," Jones said. "And it worked. Within about a month, the Zetas gave up what most analysts call a ‘sacrificial lamb' member to pay for the kidnapping."

Oliver Revell, who was head of the Federal Bureau of Investigation's Criminal Investigative Division at the time, agreed.

"We made them pay a price they didn't want to pay again," Revell told Reuters.

The sentiment was echoed on Wednesday by the current head of the same FBI division.

"Let it be known that an attack against any federal agent serving his or her country is an attack on all federal agents, and as such remains a priority for the FBI until those responsible are brought to justice," Assistant Director Ronald T. Hosko said in a statement.

(Reporting by Chris Francescani; Editing by Scott Malone and Richard Chang)