Burn soldier in retreat, reportedly in darkness (6)

I believe the answer is:

ignite

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'burn' is the definition.
(igniting is a kind of burning)

'soldier in retreat reportedly in darkness' is the wordplay.
'soldier' becomes 'GI' (term for US soldier).
'in retreat' shows that the letters should be reversed in order.
'reportedly in darkness' becomes 'nite' (I can't justify this - if you can you should give a lot more credence to this answer).
'gi' in reverse letter order is 'ig'.
'ig'+'nite'='IGNITE'

Can you help me to learn more?

(Other definitions for ignite that I've seen before include "Touch off; inflame" , "Cause to start burning" , "Catch fire; provoke" , "Cause to catch fire" , "Torch" .)

I've seen this clue in The Irish Times.

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