David Watkins, 19, turned himself in to the Fulton County Jail after a warrant was issued for his arrest, according to MARTA police. Six others have been arrested in the April 16 attack, four of which are juveniles.
A witness told Channel 2 Action News up to 30 people, mostly teens, boarded the southbound train at the Garnett Station in downtown Atlanta on the night of the attack and began hollering and screaming.
According to the police report, one of the victims had a soda can smashed in his face and his wallet stolen, while the other was punched repeatedly in his face.
MARTA police interviewed the victims and launched an investigation into the incident.
MARTA police said they are still seeking several persons of interest in the attack.
Anyone with information is asked to call 404 848-4911.