Sympathised with an officer taken in by a dodgy offer

I think it could be either:

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4,3

felt for

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'sympathised with an' is the definition.
I can't judge whether this defines the answer.

'officer taken in by a dodgy offer' is the wordplay.
I cannot really see how this works, but
'officer' could be 'lt' (abbreviation for lieutenant) and 'lt' is found within the answer.
an anagram of 'offer' is 'fefor' which is present in the left over letters.
No letters remain.
This may be the basis of clue (or it may be nonsense).

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I've seen this clue in the Evening Standard.

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