baghdad iraqi force launch offensive recapture last patch iraqi territory still hand islamic state military say wednesday security force come liberate say leaflets drop iraqi air force western border region al-qaim rawa accord statement joint operations command baghdad militant group also hold part syrian side border area control shrink retreat face two set hostile force u.s.-backed kurdish-led coalition syrian government troop foreign shi ite militias back iran russia islamic state self-declared cross-border caliphate effectively collapse july u.s.-backed iraqi force capture mosul group de facto capital iraq grueling battle last nine months militants syrian stronghold raqqa fell u.s.-backed force last week islamic state leader abu bakr al-baghdadi declare caliphate mosul mid-2014 release audio record sept. 28 indicate alive several report kill urge followers keep fight despite setbacks god us last assault daesh members say leaflets drop iraqi force border area syria refer islamic state tell among children relatives take weapon state throw aside immediately go house top white flag raise liberation force enter al-qaim iraq ready final offensive islamic state near syrian border