According to police and fire officials, three of the victims were hospitalized with life-threatening injuries.
All victims were adults and they were all outside the restaurant at the time. Three additional people were evaluated at the scene but were not transported to the hospital.
Just before noon, the car collided with the Parthenon Restaurant's outdoor seating section on Connecticut Avenue in Northwest D.C. The car's driver, an elderly man, was the only occupant. Officials stated that he was driving northbound when the car lost control.
The man cooperated with authorities and appeared to have been in an accident.
Officials said that there was no structural damage to this restaurant and that no one was trapped within.