FORT WORTH, Texas (AP) — A 16-year-old who opened fire at a Dallas-area school earlier this year, killing one student and injuring another, was sentenced Thursday to 40 years in prison for capital murder and attempted capital murder, prosecutors said.

The teen, who was 15 at the time of the shooting, had admitted to being the shooter and asked a jury to determine his sentence, the Tarrant County Criminal District Attorney's Office said in a news release. Since he's a minor, prosecutors withheld the teen's name.

Before the first bell ever rang on March 20, the teen fired a shotgun into a group of students waiting for the doors to be unlocked at Lamar High School in Arlington, prosecutors said. Ja’Shawn Poirier, 16, was killed and a 16-year-old girl was hit in the face by shrapnel.

The teen will be sent to the Texas Juvenile Justice Department and before his 19th birthday, the judge will determine if he should go to the Texas Department of Criminal Justice to serve the rest of his sentence.

Prosecutors had sought to certify the teen to stand trial as an adult, but the judge denied the request and kept him in the juvenile system.

The jury gave the teen the maximum sentence. The teen's defense attorneys had asked for leniency, saying the teen had basically raised himself.

Earlier this month, federal prosecutors said the teen's father was sentenced to over six years in federal prison for being a felon in possession of a firearm. They said following the school shooting, law enforcement searched the man's apartment and found paperwork for the shotgun recovered from the shooting and other firearms.