Robber in group seizing equipment (7)
I believe the answer is:
brigand
'robber' is the definition.
(I've seen this before)
'group seizing equipment' is the wordplay.
'group' becomes 'band' (band can mean a group of people).
'seizing' indicates putting letters inside.
'equipment' becomes 'rig' (rig is a kind of equipment).
'band' placed around 'rig' is 'BRIGAND'.
'in' is the link.
(Other definitions for brigand that I've seen before include "Highway robber" , "Freebooter" , "Gang member" , "Outlaw" , "Pirate" .)