Chicago police said Thursday that Patrick Waldon, 31, sat next to the victim, a 30-year-old man, on a train and robbed him. Police said Waldon shot the victim in the back during a struggle over the victim's backpack.
Paramedics responded to the shooting Wednesday at about 10:45 a.m. at the station in the 400 block of South Halsted Street. A 30-year-old man was transported to Stroger Hospital in serious condition, police said.
Interim Supt. Charlie Beck speaks on CTA shooting
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The shooting suspect fled west from the platform with the victim's bag and wallet. He was taken into custody following a traffic stop on the city's West Side.
Waldon has been charged with one count of aggravated battery/discharge of a firearm, one count of armed robbery, one count of armed habitual criminal and one issuance of a warrant.
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Police said since 2005, Waldon has been arrested 14 times and he has four felony convictions on his record. He was on parole for armed robbery.
The shooting came just one day after a popular street performer was stabbed at the Jackson Red Line station in the Loop.
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The 26-year-old man was stabbed multiple times, but is expected to recover. Officers arrested the woman who attacked him nearby after a witness identified her.
Last week, Mayor Lori Lightfoot responded to stats showing a surge in crime on trains and buses. Kenneth Franklin, president of the union that represents CTA rail works, said more needs to be done to improve safety.
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As for the rise in crime on CTA trains and buses, Interim Supt. Charlie Beck is planning to meet with CTA officials Friday. The meeting was scheduled before the latest incident.