A Lynn man was ordered held without bail today at his Roxbury District Court arraignment for his alleged role in the May 8 homicide of 14-year-old Jaewon Martin and the non-fatal shooting of a 15-year-old boy in Jamaica Plain, Suffolk County District Attorney Daniel F. Conley said.

RAMON SILVELO-MILES (D.O.B. 11/30/89) is charged with murder, assault and battery with a dangerous weapon, and unlawfully carrying a loaded firearm for his role in the shooting. A warrant for his arrest was approved last week in the course of a far-reaching investigation by the homicide units of the Boston Police Department and Suffolk DA’s office, and he was taken into custody Friday by members of the Boston Police Fugitive Unit.

Silvelo-Miles is the second suspect to be charged in Martin’s death: the alleged gunman, TIMOTHY HEARNS (D.O.B. 3/13/90), was arrested on July 30 and was also ordered held without bail.

Assistant District Attorney Edward Krippendorf told the court that at about 3:40 p.m. on May 8, Martin and the surviving victim were walking to the basketball court located at Columbus and Heath Streets in the area of the Bromley-Heath housing development. As they walked, they stopped to talk to two young female acquaintances.

Krippendorf told the court that gang members associated with Heath Street are known to socialize in this area.

“Jaewon Martin, however, was an eighth grade honor roll student at the Timulty Middle School and [was] not a member of the Heath Street gang,” he said.

At the same time that the victims were playing on the basketball court, Hearns “was travelling to the Bromley-Heath development. Hearns went along with Ramon Silvelo-Miles and other individuals in two vehicles to Heath Street,” Krippendorf said.

One of those vehicles belonged to Silvelo-Miles.

Krippendorf told the court that Silvelo-Miles, Hearns and other individuals with them are known associates of a rival gang that is engaged in a long-standing rivalry with associates of Heath Street.

“Silvelo-Miles and his group were going to the Heath Street area for the purpose of shooting someone from the Heath Street gang,” he said.

Upon arriving in the Heath Street area, the defendants and their associates observed Martin and the surviving victim on the basketball court. They parked nearby, and Hearns got out of one of the cars, Krippendorf said.

As Hearns approached the basketball court, Krippendorf said, he drew a loaded revolver and began firing at the victims, striking Martin fatally in the chest, and the surviving victim in the chest and the arm.

“At that point, Hearns fled the basketball court and returned to where he had come from, getting into Silvelo-Miles’ vehicle. The two vehicles then immediately fled the area as Jaewon Martin collapsed on Columbus Avenue,” Krippendorf told the court.

Martin was transported to Brigham and Women’s Hospital, where he died of a gunshot wound to his chest; the surviving victim was transported to Children’s Hospital and treated for gunshot wounds to his chest and arm that were not life-threatening.

In the aftermath of the shooting, Krippendorf said, Silvelo-Miles allegedly made statements admitting to his role in the incident. Those statements were corroborated by surveillance camera footage that showed Silvelo-Miles’ car in the area and cell phone records that placed him in the area at the time of the shooting.

The investigation into Martin’s fatal shooting remains open and very active. Persons with information on the shooting can call the Boston Police CrimeStoppers tip line at 1-800-494-TIPS. They may also text their information to investigators by texting the word “TIP” to CRIME (27463). All tipsters may remain anonymous if they wish.

Silvelo-Miles is represented by attorney John Galvin. He is due to return to court on September 2.