What may be used to identify body of old murder victim? (5)

I believe the answer is:

label

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'identify body of old murder victim?' is the definition.
'label' can be an answer for 'identify' (thesaurus). I'm not certain of the 'body of old murder victim?' bit.

I can't explain the remainder of the clue.

Can you help me to learn more?

(Other definitions for label that I've seen before include "Tag or designation" , "Name-tag" , "Tag, tab" , "Tag or trade name" , "Designate" .)

I've seen this clue in The Telegraph.

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