Gabriel fired shot - they fired back (5,7)

I believe the answer is:

rifle brigade

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'they fired back' is the definition.
I know nothing about this answer so I can't judge whether this works.

'gabriel fired shot' is the wordplay.
'shot' is an anagram indicator.
'gabriel'+'fired'='gabrielfired'
'gabrielfired' is an anagram of 'RIFLE BRIGADE'.

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