Do not assume that someone else has already reported it.
When calling 911 first tell them who and where you are, and then do the S.A.L.U.T.E.
Provide the following information in this order:
S - Size (How many suspects are there)
A - Activity (Describe what the suspects are they doing)
L - Location (Provide exact location of the suspects / incident)
U - Uniform (Provide physical description of the suspect/s; gender, age/s, clothing and footwear)
T - Time (Provide the time, speed, and duration of activity)
E - Equipment (Describe any vehicles, make, color, license plate, camera, weapons, etc.)
Use clear explanations and descriptions.Keep it brief and to the point. Try to remain neutral and not let your emotions get the best of you.
Do not hang up the phone!
Let the person receiving the information hang up the phone first.