CHICAGO (CBS) — If you’re headed to U.S. Cellular Field on Thursday night for the White Sox game, be careful. Police have issued a warning that robbers are targeting people using the Red Line, demanding money and threatening physical violence.

CBS 2’s Mike Puccinelli reports police said there have been at least four robberies near or in the Sox-35th Red Line station in late August and early September:

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  • A robbery just outside the 33rd Street entrance of the station at about 1 p.m. on Aug. 28;
  • a robbery just outside the 35th Street entrance at about 8:10 a.m. on Aug. 30;
  • a robbery inside the 35th Street lobby of the station at about 10:10 a.m. on Sept. 4;
  • and another robbery just outside the 33rd Street entrance at about 11:20 a.m. on Sept. 12.

In each case, one or two men approached the victim, who threatened them with violence if the victim did not hand over their money. Police said, in at least one case, the robbers did use physical force.

Investigators said the descriptions of the robbers have varied in each case

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Regular riders of the Red Line vowed to be more vigilant.

“I feel like that could happen anywhere but you just have to be aware, and you have to be present in the moment, and just know what’s happening around you,” Jacob Bogart said.

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Police have not said if officers have stepped up patrols near the station, although police presence will be higher this weekend with the White Sox playing their final four games of the year against the Royals.