The two vehicles collided on Weaver near Peachtree at around 6:30am.
According to an HPD spokesperson, one officer, traveling by himself, slammed into the rear end of another squad car that had two officers inside.
Both cars sustained heavy damage. Rescue teams had to use the Jaws of Life to pry open the door on one of the vehicles.
The solo officer sustained the worst of the injuries, suffering a serious neck injury. One officer from the unit hit in the rear also suffered neck and back pain. Both were taken to Memorial Hermann Hospital. The third officer wasn't transported.