The point of an arrest (4)
I believe this is a double definition.
'the point' is the first definition.
('stop' can be a synonym of 'point')
'an arrest' is the second definition.
'of' is the link.
(Other definitions for stop that I've seen before include "Pack it in - bar", "Halt; finish", "End or pause", "Finished", "Put an end to".)