CHICAGO (CBS) — Chicago Police have issued an alert about a rash of robberies in the West Loop, in which the perpetrators pretend to be police officers or security guards.

As WBBM Newsradio’s Bob Conway reports, the two fake cops and/or guards have been coming up to people either walking or sitting in vehicles, and showing or implying they had a gun.

LISTEN: WBBM Newsradio’s Bob Conway reports

The first robbery happened around 2:15 a.m. on Jan. 27 in the 200 block of North Green Street, the second about 1:25 a.m. April 1 in the 900 block of West Randolph Street, and the third at 12:33 a.m. just this past Tuesday in the 1100 block of West Randolph Street.

The suspects are described as black men between 35 and 45, the alert said. They are between 5-foot-10 and 6 feet, and weight 200-250 pounds, police said.

Anyone with information is asked to call Area Central detectives at (312) 747-8382.

The Sun-Times Media Wire contributed to this report.

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