DEERFIELD, Ill. (CBS) — During the last six weeks, three bikes have been stolen from a Metra train station in Deerfield.

In two of the most recent cases, CBS 2’s Suzanne Le Mignot reports, Deerfield police say surveillance video shows teens coming to Deerfield on trains, from Chicago. They get off, find a bike that they like, cut the locks.

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Then they get right back on the train, with the bike.

“There are juveniles that are coming up and we have identified them. It is still an active investigation, but they are captured on the surveillance video,” said Detective  Brad Schroeder of the Deerfield Police Department. “We are definitely in the process of working with the juvenile court system to take them into custody on the crime.”

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Schroeder says an increase in bike thefts over the Summer is common. He says his department has stepped patrols at the train station.

“It’s something that we want to get awareness out to the public. Let them know. It’s the oldest thing in the world. If you see something say something,” Schroeder added.

Schroeder said he’d advise cyclists who lock their bikes up at the train station to “’Use a quality lock. It’s something that’s easily preventable. Use a quality lock. You have $1000 bike spend a little bit extra money and get something that’s less likely of getting cut.”

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One of the things that the suspects are doing is selling the bikes for the fraction of the original cost.

Suzanne Le Mignot