People out - on patrol? (7)

I believe the answer is:

pickets

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'people' is the definition.
(picket is a kind of person)

'out on patrol?' is the wordplay.
'out' becomes 's' (I can't justify this - if you can you should believe this answer much more).
'on' means one lot of letters go next to another.
'patrol?' becomes 'picket' (I have seen 'Small patrol ' mean 'picket' so perhaps 'patrol' could also mean 'picket').
's' after 'picket' is 'PICKETS'.

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I've seen this clue in The Globe and Mail.

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