By CBS 2 Chicago Staff

CHICAGO (CBS)– A person of interest was taken into custody on Friday after multiple pistol-whipping attacks on the CTA Blue Line.

Police said an air-soft pistol was recovered from the person of interest’s backpack. Charges are pending.

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On August 4, shortly before 9 a.m., a man riding a northbound Blue Line train struck a 39-year-old woman in the head and arm with a handgun. He then got off the train at the Western stop on the 1900 block of North Western Avenue, and fled the scene.

The woman was taken to AMITA Health Saints Mary and Elizabeth Medical Center Chicago for treatment, and was listed in good condition, police said.

A similar incident took place on the Blue Line at Clinton Avenue on August 2.

Chicago Police later released surveillance images of the attacker, who also was seen “removing a firearm from his bag and striking CTA passengers in the head” in other attacks on CTA trains.

On Monday morning just before 7 a.m., police said a man fitting the same description attacked another passenger near the platform at the Clinton stop in the West Loop.

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The attacks are all random. One man said they “definitely” come as a concern to him as a Blue Line passenger.

“It’s definitely a concern,” he said. “There should never be violence on the CTA.”

CBS 2 asked that man whether he ever sees police officers on the trains when he is on board. He said he never had.

In each attack, the man took off before officers could catch him. The incident near the Bucktown and Logan Square communities on Wednesday left Blue Line riders uneasy.

“The only thing we can do is be alert and report it if we see something,” a woman said.

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There has been no mention of the man robbing passengers – only assaulting them and then running away.

CBS 2 Chicago Staff