CHICAGO (CBS) — Police warned the public Sunday evening about a group of men who have been driving around Hyde Park and robbing people.

Two incidents have been reported so far – both within one 24-hour period on Friday. Three to four men got out of a vehicle, came up to the victim on foot, and demanded property.

The robbers took property and drove back off, police said. In one instance, a robber punched a victim in the neck.

In one robbery, the assailants drove off in a black vehicle, while in the other they used a beige sedan.

The first robbery happened at 2 a.m. Friday in the 5300 block of South Dorchester Avenue. The second happened at 9:15 p.m. Friday in the 5400 block of South Blackstone Avenue.

Police advised that people be aware of their surroundings, report suspicious activity immediately, remain calm if confronted by an assailant, remember unique physical characteristics, never chase a suspect, request contact information if approached by a witness, and call 911 immediately and remain on the scene when possible.

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