A young man was behind bars Tuesday in connection with the death of a teenage boy who was gunned down last spring while hanging out with friends at a San Marcos strip mall.

Members of a federal fugitive task force arrested Adrian Francisco Ramirez, 19, on Friday at San Ysidro Port of Entry for allegedly murdering 17-year-old Isaac Shekhayem of San Marcos, according to the San Diego County Sheriff’s Office.

The gunman got away, reports NBC 7’s Audra Stafford.

At about 11:30 p.m. on May 15, the boy was standing with a group of people in a parking lot at a shopping center in the 900 block of Los Vallecitos Boulevard when a vehicle pulled to a stop nearby and the shooter stepped out and opened fire.

A round struck the victim in the head, mortally wounding him, sheriff’s Lt. Michael Krugh said. One of the victim’s companions drove him to Palomar Medical Center, where he was pronounced dead shortly after arrival.

Officials did not immediately disclose what led investigators to identify Ramirez as the alleged shooter.

On Tuesday, Ramirez, also a San Marcos resident was arraigned and pleaded not guilty to charges of murder and shooting at an occupied motor vehicle. He faces up to 50 years to life in state prison if convicted of all counts.