By CBS 2 Chicago Staff

CHICAGO (CBS) — A group of men robbed three 7-Eleven convenience stores downtown in a span of 30 minutes on Monday morning, Chicago Police said.

Four black males first robbed the 7-Eleven in the 0-100 block of East Lake Street at 8:29 a.m. They were armed, demanded money and took an undetermined amount of cash before fleeing in a black vehicle, police said.

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Five minutes later, police believe the same group wearing masks and hooded sweatshirts, hit the 7-Eleven in the 0-100 block of East Wacker. They stole cash and merchandise, police said.

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Then, just before 9 a.m., the crew robbed the 7-Eleven in the 300 block of South State. Someone in the group displayed a gun and took money, police said.

They got into a parked SUV and fled in an unknown direction.

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No injuries were reported. No one is in custody at this time. Area Three detectives are investigating.

CBS 2 Chicago Staff