Feud in event at ground interrupted by leader of district (8)
I believe the answer is:
vendetta
'feud' is the definition.
(vendetta is a kind of feud)
'event at ground interrupted by leader of district' is the wordplay.
'ground' indicates anagramming the letters (grind the letters ).
'interrupted by' indicates putting letters inside.
'leader of' suggests taking the first letters.
The first letter of 'district' is 'd'.
'event'+'at'='eventat'
'eventat' with letters rearranged gives 'venetta'.
'venetta' enclosing 'd' is 'VENDETTA'.
'in' acts as a link.
(Other definitions for vendetta that I've seen before include "Bitter feud between families" , "Long bitter row" , "Unremitting battle" , "ongoing row" , "A bitter Italian feud" .)