A 15-year-old from Chicago has been charged with robbery and four suspects remain at large after the early-morning robbery of a cell phone outside the Austin Boulevard stop of the CTA Green Line on June 23, police said.

Here’s how it went down: The 24-year-old victim was exiting the station around 12:30 a.m. when someone from a group of five guys punched him in the face and wrestled him to the ground. Someone then grabbed his cell phone. A witness to the incident called police, and at about the same time, the victim got up and chased the five south on Austin Boulevard.

Police saw the foot chase and caught up with one of the suspects on Austin between Randolph Street and Washington Boulevard, Det. Cmdr. LaDon Reynolds said. The youth was arrested after the victim positively identifed him as one of his assailants.

The victim scraped his left knee and right wrist and his face was slightly swollen during the attack, but did not require medical treatment at the scene, Reynolds said. The phone was valued at $100.

The incident came shortly after the Chicago Tribune reported that the CTA Green and Blue lines were found to be crime hotspots. The analysis was part of a larger Tribune examination of crime on the CTA.  

Earlier: Blue Line, Green Line Land on List of CTA Crime Hotspots

Crimes had been found to be pervasive on the Green Line, particularly at the Pulaski stop, which is in the middle of an Oak Parker's commute.

To help combat the crime, police in Oak Park have long been part of the CTA's Secondary Employment Detail, a grant program that pays for an Oak Park police presence at transit stations, bus routes and rail cars.

The officers typically patrol the stops along the Blue and Green Lines or they'll hop aboard train cars during rush hour, generally from 2-8 p.m.