By Elizabeth Hur

PHILADELPHIA (CBS) – A teenager accused of opening fire on a Septa train is in custody after the boy’s parents turned him over to police Thursday afternoon.

Police confirm, in addition to the 16-year-old male brought in on Wednesday, a 15-year-old boy, the suspected shooter, is now in custody in connection with the shooting of two teenagers on the Broad Street train at the Dauphin Street stop in the middle of the day on Wednesday.

Capt. Sharon Seaborough with the Philadelphia Police Department said, “It’s so sad that the parents had to surrender their child to be arrested for aggravated assault and not knowing what the outcome is going to be. That has to be heart wrenching.”

Heart wrenching and senseless, police say, when you consider a14-year-old boy remains in critical condition at Temple University Hospital. The second victim, a 17-year-old male has since been treated and released. The two, according to investigators, fell victim to gunfire motivated by what appears to be the result of a prior altercation.

Lt. Patrick Doherty explained, “It had nothing to do with the schools, it was individuals that just happened to meet up on the train, words were exchanged, this one individual, one juvenile fired into the train striking two people.”

Lt. Ron Coates with Septa Transit Police added, “We’re out there day and night, 24/7, the men and women of our department keep this system as safe as they can.”

Septa officials say their message is simple: Septa is safe. Philadelphia police agree and hope this speedy arrest will send a stern message to other teenagers looking for trouble.

Capt. Seaborough said, “It’s so nice that the parents cooperated but I can just imagine what they’re going through and maybe the kids should understand, not only is this going to affect his future but it’s going to affect his family too.”

According to sources, this is the suspected shooter’s fourth arrest. Sources tell Eyewitness News, the suspect was arrested in 2010 for assault, in 2011 for retail theft then just two days ago for narcotics.

This time around, police say just as soon as investigators got a hold of the suspect’s parents, they brought him in within 90 minutes.

Police say the 15-year-old could face a judge as early as Friday to answer to charges of Aggravated Assault, Simple Assault, Recklessly Endangering Another Person and related offences.

As of Thursday night, the 16-year-old also in custody had not been charged. Police say charges against him are pending as their investigation is continuing.

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