Range of humankind observed in crowd disturbance (5,4)
I believe the answer is:
rifle shot
'range' is the definition.
(rifle shot is a kind of range)
'humankind observed in crowd disturbance' is the wordplay.
'humankind' becomes 'flesh' (I can't justify this - if you can you should believe this answer much more).
'observed in' means one lot of letters goes inside another.
'crowd disturbance' becomes 'riot' (I've seen this before).
'flesh' inserted within 'riot' is 'RIFLE-SHOT'.
'of' acts as a link.
Can you help me to learn more?
(Other definitions for rifle shot that I've seen before include "Act of sniper" , "Bullet" , "report" , "Feature of war" .)