A woman in her 60s and another in her 20s were transported from the scene in critical condition, and Phoenix Police Department Sgt. Steve Martos said one of them later died. Another woman and a man in his 20s suffered non-life threatening injuries in the shooting, Martos said.
Martos believes there are as many as four suspects involved in the shooting, and their vehicle is being described as a 2000-2006 dark green Ford Expedition.
Video from a news helicopter showed one of the victims in the driveway of the house being surrounded by law enforcement, placed on a stretcher and put into an ambulance.
None of the victims' names were immediately released.
Martos said it's unclear if any of the victims were related. He wouldn't speculate if the incident was gang-related or if the victims were targeted.
Arizona Department of Public Safety officers were assisting Phoenix police in the search for the shooter.
At the scene, police marked at least 20 bullet shell casings with white evidence markers in front of the home and on the roadway. All the windows at the single-story brick house appeared to be covered with tin foil.
The Associated Press contributed to this story