According to Chicago police, around 4:20 a.m. the bus was traveling eastbound on Washington Street when a black sedan traveling at a "high rate of speed" southbound on Clark, ran through a red light and crashed into the bus, causing it to strike the side of a bank building.
The bus driver was pinned under the dashboard and had to be extricated by firefighters, fire officials said. The driver was transported to Northwestern Hospital in critical but stable condition.
Two bus passengers were also transported to Northwestern for treatment, officials said. They are in fair condition.
The driver of the sedan was identified as a 29-year-old man, police said. He was not injured in the crash.
Citations are pending.
No further information has been released at this time.