CHICAGO (CBS) — Chicago police are warning about a group of robbers attacking people.

Here you see three of the suspects, but there could be up to four of them.

In a community alert, police say the criminals push or punch the victims before robbing them. Then they take off on foot.

The group has already struck three times this month.

On Delaware, Chestnut and Huron, in River North and the near North Side. Police say people should always be aware of their surroundings and if confronted by an assailant to remain calm.

Police ask that people provide specific information to authorities, including to remember any unique physical characteristics like tattoos, scars, acne, etc.

Anyone with any information on the suspected robbers is asked to contact Area Central detectives at 312-747-8380.