Various sergeants etc. becoming spies (6,6)

I believe the answer is:

secret agents

'spies' is the definition.
(I've seen this before)

'various sergeants etc' is the wordplay.
'various' is an anagram indicator.
'sergeants'+'etc'='sergeantsetc'
'sergeantsetc' anagrammed gives 'SECRET AGENTS'.

'becoming' is the link.

(Another definition for secret agents that I've seen is " Spies".)

I've seen this clue in The Times.

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