Close watch of criminal clan, evil? Sure (12)

I believe the answer is:

surveillance

I'm a little stuck... Click here to teach me more about this clue!

'close watch' is the definition.
'surveillance' can be an answer for 'watch' (surveillance is keeping watch). I'm not sure about the 'close' bit.

'criminal clan evil? sure' is the wordplay.
'criminal' indicates an anagram.
'clan'+'evil'+'sure'='clanevilsure'
'clanevilsure' with letters rearranged gives 'SURVEILLANCE'.

'of' is the link.

Can you help me to learn more?

(Other definitions for surveillance that I've seen before include "Watch" , "Covert observation" , "Close observation" .)

I've seen this clue in The Times.

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