The crash happened near 79th Street and Maryland Avenue in Grand Crossing.
Chopper 7 was over the scene around 8:30 a.m. Two silver SUVs were involved in the crash with a westbound No. 79 bus, the CTA said.
The Chicago Fire Department along with other first responders were there.
CFD said children and adults were among the 13 transported to area hospitals.
All were expected to be OK.
It is unknown what led to the crash. Chicago police have not released more information.
READ ALSO | Chopper 7 over crash in suburban Oak Lawn involving airport shuttle bus