Jobcentre attacked holding petition (7)
I believe the answer is:
entreat
'petition' is the definition.
(thesaurus)
'jobcentre attacked holding' is the wordplay.
'holding' says the answer is hidden in the clue.
'ENTREAT' can be found hidden inside 'jobcentre attacked'.
(Other definitions for entreat that I've seen before include "Sue" , "Ask (someone) anxiously" , "Pray" , "Beg earnestly, appeal" , "Beg earnestly, implore" .)