Police information on risks involving millions (9)
I believe the answer is:
gendarmes
'police' is the definition.
(branch of French police)
'information on risks involving millions' is the wordplay.
'information' becomes 'gen' (gen can informally mean information).
'on' is a charade indicator (letters next to each other) (in a down clue, letters appear on others).
'risks' becomes 'dares' (I've seen this before).
'involving' indicates putting letters inside.
'millions' becomes 'm' (abbreviation).
'dares' enclosing 'm' is 'darmes'.
'gen'+'darmes'='GENDARMES'
(Other definitions for gendarmes that I've seen before include "soldiers" , "French policemen" .)