Police are warning North and Near North Side residents of a series of robberies reported in River North, Lincoln Park and the Gold Coast.

In each case, the suspects either threatened violence or attacked someone before taking their property, Chicago police in an alert.

The thefts happened:

In the morning hours of Aug. 25 in the first block of West Elm Street

In the morning hours of Aug. 31 in the 1100 block of North Lasalle Drive

In the morning hours of Sept. 7 in the 200 block of West Ontario Street

In the evening hours of Sept. 10 in the 300 block of North State Street

In the morning hours of Sept. 11 in the 400 block of North Dearborn Street

In the afternoon hours of Sept. 28 in the 700 block of North Wabash Avenue

The suspects are described by police as three to five men between the ages of 20 and 25.

Anyone with information is asked to call Area Central detectives at 312-747-8380.

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