A 15-year-old Hyde Park girl was arrested in an assault on an MBTA bus driver by more than a dozen people last weekend, Transit Police said Thursday.
The arrest is the second in the attack, in which authorities say a group of teenagers flagged down a Route 16 bus on Columbia Road in Dorchester on March 9, stormed the bus, and beat the 53-year-old driver while another group attacked the MBTA driver from outside, through the bus window.
Because detectives are continuing to investigate the crime and identify other perpetrators, officials are not releasing information about how the 15-year-old was caught, said MBTA spokeswoman Kelly Smith.
On Wednesday, police arrested Albert Galloway, 18, of Roxbury after an anonymous tipster told a Transit Police officer he heard Galloway talking about beating up the driver.
Police later found a Twitter account they believe belongs to Galloway and a post that read, “My hands hurt from last night.”
During his arraignment Wednesday, Galloway pleaded not guilty to several charges, including assault and battery. He was ordered held on $15,000 cash bail.
His attorney, Andrea McGeehan, said her client was riding on the Route 16 bus and punched the driver, but only because he was also being attacked by the group. McGeehan said that after being struck from behind, Galloway wheeled around and threw a punch that mistakenly landed on the bus driver.
But Joseph F. O’Connor, Transit Police superintendent in chief, said Wednesday that Galloway’s claim of self-defense is not supported by video footage from a nearby building that caught some of the altercation.
The driver, who was punched and kicked by the assailants and who has not been named to protect his identity, was taken to Boston Medical Center, where he was treated and released.
The 15-year-old Hyde Park girl is expected to be arraigned Friday in Dorchester Juvenile court.