Attack loudly, on public walk (4)
I believe the answer is:
mall
'public walk' is the definition.
(I've seen this before)
'attack loudly' is the wordplay.
'attack' becomes 'maul' (to maul is to viciously attack).
'loudly' indicates a 'sounds like' (homophone) clue (when spoken - not silently).
'maul' sounds like 'MALL'.
'on' is the link.
(Other definitions for mall that I've seen before include "Sheltered walk or promenade" , "Covered complex of shops or path by a canal" , "Glowing material in fire" , "Shopping precinct" , "Mercantile centre" .)