So report unruly soldiers (8)
I believe the answer is:
troopers
'soldiers' is the definition.
(trooper is a kind of soldier)
'so report unruly' is the wordplay.
'unruly' is an anagram indicator.
'so'+'report'='soreport'
'soreport' with letters rearranged gives 'TROOPERS'.
(Other definitions for troopers that I've seen before include "Swearing 19 Downs [SOLDIERS]" , "Cavalrymen" .)