According to Phoenix Police Sgt. Trent Crump, a son and his mother were fighting inside of a vehicle in the area around 10:30 p.m.
At some point, the son reportedly began stabbing his mother in the vehicle, and she eventually fell out near the intersection.
Crump says several people tried to help her, but were unable to get the son to stop. A neighbor eventually grabbed a handgun and shot him.
Police say the son was declared dead.
The mother was taken to a hospital in critical condition.This is a developing story. Stay with FOX 10 News for updates.