OAK LAWN, Ill. (CBS) — Security video captured it all, and now police believe the man who robbed an Oak Lawn gas station last week might also be responsible for at least two other robberies.

Marathon gas station owner Abdul Halani said the suspect walked into his shop at 107th Street and Cicero Avenue on Tuesday night, wearing a mask.

On the surveillance video, the suspect can be seen approaching the clerk, pulling out a blue steel gun, and demanding money. The clerk steps away from the register, and the suspect is seen stuffing money into the same bag. Then, he walks out, with a limp.

Halani, who has owned the station for just a few months, said the robber got away with about $600.

Cook County Sheriff’s dogs tried to track the suspect’s scent, but lost it after a few blocks.

Oak Lawn Police Chief of Detectives Mike Kaufman said police are now investigating the possibility the same man might have robbed two other gas stations in Chicago a few days prior to this robbery.

Kaufman said the suspect’s clothes and pattern of behavior matched those in the other robberies. He’s asking anyone with any information to call police.

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