"That officer is in a very, very tough place; unimaginable what that officer has to be feeling right now," Chicago Police Supt. Larry Snelling said.

Krystal Rivera, a 36-year-old single mother who had spent four years on the force, was rushed to the hospital in a squad car after taking a gunshot wound to the back. The vehicle she was traveling in bizarrely crashed and caught on fire, and she had to be transferred into another vehicle to complete the journey.

Chicago police officials say an officer killed this week was accidentally shot and killed by her partner after they encountered someone with a rifle when they chased a suspect into an apartment.