Stop and apprehend (6)
I believe the answer is:
arrest
I believe this clue is a double definition.
'stop' is the first definition.
(synonyms)
'apprehend' is the second definition.
(synonyms)
'and' acts as a link.
(Other definitions for arrest that I've seen before include "Apprehend; detain" , "Take into custody as police do" , "Cause to stop" , "Stop (on suspicion)" , "Stop - detain" .)