A 16-year-old boy was charged Tuesday with beating three Red Line passengers last month at a platform on the Near North Side, making him the fifth teen arrested in connection with the mob attack.

He faces felony counts of aggravated battery causing great bodily harm, mob action with more than two people and aggravated battery in a public place, according to a press release from Chicago police.

An anonymous tipster identified the boy as one of the dozen or so aggressors from the Dec. 19 attack at the Chicago Avenue station, police said. He was arrested about 1:15 p.m. Monday in the 6200 block of South Stony Island Avenue in Woodlawn.

The victims were waiting for a train about 7:30 p.m. when the group of teens stepped onto the platform, police said. One of the people in the group asked a 26-year-old man if he was recording them, which he denied.

The horde of teens then approached the man, a 29-year-old woman and her 28-year-old boyfriend and started punching them, according to police and the victims.

All three were treated at the scene for bruising and lacerations, according to Chicago Fire Media Affairs.

The 28-year-old, who has lived in Chicago for three years, said he later went to University of Illinois Hospital, where he learned that his eye socket was fractured.

In the days following the attack, authorities released surveillance photos of multiple suspects.

Since then, three teenage boys and one man were identified and handed felony charges.

The 16-year-old who was arrested Monday is scheduled to appear in juvenile court on Tuesday. His identity was not released because he is a juvenile.