Chicago police said two squad cars collided while responding to an officer needs assistance call at around 7:30 p.m.
Investigators said a marked squad car carrying two officers and an unmarked squad car with four officers crashed into each other in the intersection Springfield Ave. and Jackson Boulevard.
A Chicago Fire Department official said four officers were transported to Stroger Hospital, and two others self-transported Saturday.
It remains unclear if the officers' conditions have been upgraded, or how long they'll be hospitalized.
Major Accidents Unit is investigating the incident.
No other details are known at this time.