A man in this country illegally when he allegedly shot and killed a 16-year-old Baton Rouge boy on the teen's birthday in March pleaded not guilty Thursday to a negligent homicide charge.

Octavio Bringas-Posadas, 50, a Mexican national, was indicted on that charge last month by an East Baton Rouge Parish grand jury.

Bringas-Posadas, told a relative he was playing with a gun inside his Southpark Drive apartment off Airline Highway when it fired by accident, striking Darius Plummer, authorities have said.

Plummer was the best friend of Bringas-Posadas' son.

State District Judge Lou Daniel on Thursday appointed the East Baton Rouge Parish Public Defenders Office to represent Bringas-Posadas, who said he had no money to hire a lawyer.

Bringas-Posadas, who pleaded guilty in June to federal gun and immigration charges stemming from the fatal March 13 shooting, has not been sentenced and remains in federal custody.

He was deported to Mexico in 2012 after a Baton Rouge drug arrest but later found his way back into the U.S.

Bringas-Posadas faces up to 12 years in federal prison on the charges he pleaded guilty to June 7 — illegal re-entry into the United States, and possession of firearms and ammunition by a person illegally in this country.

U.S. District Judge Shelly Dick has told Bringas-Posadas he will likely be deported as a result of his guilty pleas in federal court.

He faces up to five years in prison if convicted of negligent homicide. His next court date in state court is Sept. 26.

Follow Joe Gyan Jr. on Twitter, @JoeGyanJr.