CHICAGO (CBS) — A man was shot and killed outside the Garfield station on the CTA Red Line early Monday, and the suspected gunman was arrested a few minutes later, police said.

Chicago Police Chief of Detectives Melissa Staples said the shooting was caught on surveillance video. The victim and the gunman were seen arguing on the platform of the Garfield station around 2:30 a.m., and CTA employees asked them to leave.

“The argument continued outside the doors of the station vestibule. The offender then produces a handgun, per the video, and chases the victim across the street, subsequently shooting and killing him,” she said.

Witnesses said they heard five or six shots.

“I was at the Citgo, and I heard like five, six gunshots go off, and then two cars sped off, and there was a guy laying on the ground. I think they robbed him. They took his jewelry and money, and left him laying on the ground,” Toni Gatto said.

The victim, a 33-year-old man, was shot in the head and chest. Paramedics took him to Stroger Hospital, where he was pronounced dead.

Shortly after the shooting, a description of the gunman was provided to patrol units over police radios, and Deering District officers spotted the suspect and arrested him a few minutes after the shooting, according to Staples. A firearm also was recovered.

Staples said the suspect in custody has not given a statement, so police do not yet know the motive for the shooting, or if the victim and the gunman knew each other before the argument at the Red Line station.

Chicago Police Chief of Patrol Fred Waller said he has ordered increased patrols at CTA stations, but sought to reassure riders they should feel safe using the CTA.

Some Red Line riders suggested the CTA also should add more guards and cameras.

“It’s a lot going on. They’re selling loose cigarettes. They’re selling drugs throughout the train as we’re riding, even standing outside here. It’s not too safe,” Roosevelt Smith said. “I thought about just catching the bus instead of the train this morning, I really did.”

No charges had been filed as of late Monday morning. Area Central detectives were investigating.

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