I just experienced a Hit and Run. Immediately, I realized that they were not going to stop and I then pursued to get the tag number reaching speeds over 100 mph hoping that a cop would get involved. While in pursuit, I called 911 and advised them of what occured and what my actions were and was advised to not follow but to get the tag number. I was able to catch up to the vehicle and get the tag number. After catching up to the vehicle, I unknowingly entered another district and again called 911. An Officer responded and advised that the accident occured oustide of his district and that he could do anything and gave me the number to APD.