They'd collared criminal without pity (4-9)

I believe the answer is:

cold-heartedly

'without pity' is the definition.

'they'd collared criminal' is the wordplay.
'criminal' indicates anagramming the letters.
'theyd'+'collared'='theydcollared'
'theydcollared' anagrammed gives 'COLD-HEARTEDLY'.

(Other definitions for cold-heartedly that I've seen before include "In a callous manner" , "Callously" .)

I've seen this clue in The Everyman puzzle in The Observer.

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