A 50-year-old Mexican national accused of fatally shooting a Baton Rouge boy on his 16th birthday in March pleaded guilty Wednesday to federal gun and immigration charges stemming from that incident and apologized to the citizens of the United States for being in the country illegally.

Octavio Bringas-Posadas, who has been booked by the East Baton Rouge Parish Sheriff's Office on a second-degree murder count in the killing of Darius Plummer but not formally charged, faces up to 12 years in prison on the two federal counts: possession of firearms and ammunition by a person illegally in the United States and illegal re-entry into the United States.

U.S. District Judge Shelly Dick ordered a presentence investigation report but did not set a sentencing date.

The Spanish-speaking Bringas-Posadas, who was deported to Mexico in 2012 after a drug arrest, told Dick through an interpreter that he had been working for legal companies while in this country and always paid taxes. Shackled and wearing an orange prison jumpsuit, he offered an apology to the United States for committing the federal crimes, which he acknowledged was wrong.

The only reference to the shooting of Plummer, who was the best friend of Bringas-Posadas' son, came when Assistant U.S. Attorney Jessica Thornhill was asked by Dick to give a factual basis for Bringas-Posadas' federal crimes. Thornhill said Bringas-Posadas was apprehended in Calcasieu Parish on March 13 as part of a homicide investigation.

During a search of his car and Southpark Drive apartment off Airline Highway in Baton Rouge, authorities found three handguns and ammunition, the prosecutor said. Dick said Bringas-Posadas will have to forfeit the guns — a .357-caliber revolver, .22-caliber pistol and .22-caliber revolver — and ammo.

Bringas-Posadas' attorney, Assistant Federal Public Defender Mark Upton, said in court that his client does not have a plea agreement with the federal government.

Dick told Bringas-Posadas that he will "very likely be deported" as a result of his guilty pleas.

"Yes, and I will not return," he told the judge through his interpreter.

East Baton Rouge Parish District Attorney Hillar Moore III said recently his office anticipates bringing the Plummer shooting to a grand jury. Bringas-Posadas will be "kept here pending our charges or sent to a federal facility where we could always bring him back," Moore said.

Bringas-Posadas told a relative he was playing with a gun March 13 when it fired by accident and struck the teen, police have said. He was shot once. Bringas-Posadas also told the relative on the phone that he was not coming back to Baton Rouge and would not talk with police, his arrest warrant states. He was stopped on Interstate 10 in Lake Charles.

A federal grand jury in Baton Rouge indicted Bringas-Posadas on March 30. He had pleaded not guilty to the federal charges in April.

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