Summary arrest (5,2)
I believe the answer is:
round up
This clue is a double definition.
'summary' is the first definition.
(I've seen this before)
'arrest' is the second definition.
(as in rounding up suspects)
(Other definitions for round up that I've seen before include "Collect" , "herd" , "Gather together" , "rally" , "Summary" .)