Firefighters say Engine 14 was responding to a medical call with lights and sirens. As the engine was turning right, one car ran into its side. The second car rear-ended the truck just after that, police said.  

No one was injured.

The Chicago Fire Department confirmed Engine 109 was responding to a call when a van struck the back of the fire truck near 31st and California.  

Four adults and two children were taken to Mount Sinai Hospital and John H. Stroger Jr. Hospital of Cook County, all in critical condition, the fire department said.