Aidan McGuinness, 18, and two 17-year-olds, all from Quincy, are accused of the May 10 robbery at the Kenmore Square station, the Suffolk County District Attorney said. They were arrested on Friday, May 17.
Police received a call about an assault just before 10:15 p.m. and arrived to find four teenagers from Druxbury with various wounds. Three had cuts to their faces and blood coming from their mouths, and the fourth had blood on his clothes and cuts on his knuckles.
They said three teens they didn't know approached them. One lifted his shirt to show a knife tucked into his waistband. That's when the teens jumped them and threw them to the concrete, the prosecutor said.
Surveillance video backed up their story, and police recognized McGuiness from a Snapchat video of the attack that was sent to about 60 people, authorities said.
Quincy school officials helped track down the other two juveniles in the video.
McGuiness is charged with unarmed robbery and assault and battery causing serious bodily injury, the prosecutor said. He was ordered held on $1,500 bail and must stay away from the victims.
One of the juveniles was charged with two counts of assault with a dangerous weapon (knife), one count of assault and battery causing serious bodily injury, one count of unarmed robbery, and one count of assault and battery, the prosecutor said.
The other was charged with assault and battery with a dangerous weapon (cement floor), assault and battery causing serious bodily injury, and unarmed robbery, officials said.
They were both ordered held on $200 bail, the prosecutor said.
Suffolk County DA Kevin Hayden thanked the MBTA police for their quick work in solving this "brutal and unprovoked attack."
These individuals may have thought they could launch a brutal and unprovoked attack on a group of young people and get away clean, but the tenacity of transit police combined with help from the victims, the public, and video and social media evidence proved them wrong. These victims endured a terrifying experience and suffered serious injuries while doing nothing more than enjoying an evening in Boston. Their attackers will answer for their actions.
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