Chicago police are warning people in River North and the Gold Coast about a string of strong-arm robberies reported on the Near North Side.

In each incident, two teenage boys approached people on the street and punched them or snatched property from their hands, Chicago police said.

The robberies happened in the evening Aug. 3 in the 600 block of North Wells Street, in the morning Aug. 7 in the first block of West Grand Avenue and in the morning Aug. 18 in the 100 block of East Chestnut Street, police said.

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