Chicago Transit Authority spokeswoman Catherine Hosinski said the No. 3 bus was traveling on Michigan Avenue about 8:40 a.m. CDT when it was cut off by a vehicle, possibly a taxi, and the driver was forced to slam on the brakes, the Chicago Tribune said.
Several passengers were injured despite the fact the driver avoided a collision.
"It never really hit another structure,'' Chicago Fire Chief Juan Hernandez said.
The eight individuals requiring medical treatment were all listed in fair or good condition, the Tribune said.