A Hyde Park teen was sentenced to life in prison on Wednesday for the 2012 murder of a 22-year-old man in the South End, according to the Suffolk district attorney’s office.

Raymond Concepcion, now 18, was convicted in Suffolk Superior Court for the first-degree murder of Nicholas Martinez of Boston, the office of District Attorney Daniel F. Conley said in a statement.

Concepcion was also convicted of unlawful possession of a firearm in Martinez’s killing, the district attorney said.

Because he was 15 years old when he committed the murder, Concepcion will be eligible for parole after 20 years, Conley’s office said. He was also sentenced to a concurrent term of four to five years for the firearm charge, according to the district attorney.


Two other co-defendants in Martinez’s murder, Jaquan Hill, 22, and Shakeem Johnson, 25, both of Hyde Park, pleaded guilty to manslaughter on Feb. 17, Conley’s office said. They were each sentenced to 12 to 14 years in prison.

On Oct. 17, 2012, Martinez was driving in the South End and was stopped in traffic when Concepcion, then a freshman at Brighton High School, approached his vehicle and fired four shots inside, Conley’s office said.

Concepcion then returned to the back seat of a vehicle a few car lengths behind, in which Johnson was the driver and Hill was in the front passenger’s sear, the statement said.

Martinez was taken to Boston Medical Center, where he was later pronounced dead.

Martinez’s mother delivered a tearful impact statement to the court, the district attorney said.

“On the inside I’m dying,” she said. “And this pain is never going to go away. It’s never going to go away because it’s the worst thing a mother can go through.”

Martinez’s girlfriend and the mother of his child also submitted a written impact statement.


“That night everything changed. My life would no longer be the same,” she wrote. “I had to come to terms with the fact that my daughter would grow up without her loving dad, I was no longer going to marry the man I loved -- my best friend -- and his family had lost him for good.”

Brian Ballou of the Globe Staff contributed to this story. Olivia Arnold can be reached at olivia.arnold@globe.com. Follow her on Twitter @olivia_arnold12.