CHICAGO (CBS) — Police have filed murder charges after a fatal stabbing on the Red Line on Saturday. 

Tony Polk, 40, of the 7400 block of South Kingston, was arrested and charged with one count of first degree murder on Tuesday.

Tony Polk, charged with first degree murder.

A 54-year-old man was fatally stabbed after getting into an argument with another man on the train around 2:50 p.m.

The suspect got off at the Cermak stop and ran.

Persons of interest in a stabbing near Cermak on the Red Line.

Police released surveillance images of two person of interest in the case over the weekend.

According to the Illinois Department of Corrections, Polk has been convicted of armed or aggravated robbery three times, most recently in 2013. His parole date for that conviction was listed at March 7, 2019.