Second assailant sets about shop worker (5,9)

I believe the answer is:

sales assistant

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'shop worker' is the definition.
'sales assistant' can be an answer for 'worker' (I know that sales assistant is a type of employee). I am not certain of the 'shop' bit.

'second assailant sets about' is the wordplay.
'second' becomes 's' (common abbreviation).
'about' is an anagram indicator.
'assailant'+'sets'='assailantsets'
'assailantsets' with letters rearranged gives 'alesassistant'.
's'+'alesassistant'='SALES ASSISTANT'

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I've seen this clue in The Telegraph.

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