Correspondents gathering in Shanghai (5-4)

I believe the answer is:

press-gang

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

'correspondents gathering' is the wordplay.
'correspondents' becomes 'press' (I can't justify this - if you can you should give a lot more credence to this answer).
'gathering' becomes 'gang' (gang is a kind of gathering).
'press'+'gang'='PRESS-GANG'

'in' acts as a link.

Can you help me to learn more?

(Other definitions for press-gang that I've seen before include "Forcibly enlist" , "Force into service" .)

I've seen this clue in The Times.

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