CHICAGO (CBS) — Chicago police are looking for a man they say robbed another person on a CTA Red Line train in Wrigleyville last month.

The robbery happened around 9 p.m. on Oct. 22 in the 900 block of West Addison Street.

Police said the suspect forcibly took another passenger's cell phone before getting off the train at the Addison stop.

The suspect wore a blue Los Angeles basketball jersey and had a small blue bicycle with him.

Riders are advised to:

• Be aware of their surroundings
• Avoid suspicious persons
• Keep valuable belongings out of plain view

Anyone with information can contact public transportation detectives at 312-745-4447 or submit an anonymous tip at CPDTIP.com.