beirut u.s.-backed militias syria say come attack saturday russian jet syrian government force deir al-zor province flashpoint increasingly complex battlefield syrian democratic force sdf alliance kurdish arab militias fight u.s.-led coalition say six fighters wound strike pentagon say russia bomb position east euphrates river know sdf fighters coalition advisers station jet injure coalition force say immediate comment moscow damascus washington moscow support separate offensives syrian conflict advance islamic state militants eastern region border iraq force east euphrates hit attack russian aircraft syrian regime force target units industrial zone sdf say statement sdf accuse damascus try obstruct fighters attack waste energies use terrorism ... open door side conflict say assault russian-backed syrian army u.s.-backed sdf time raise fear clash could stoke tensions compete world power offensives converge islamic state opposite side euphrates river bisect oil-rich deir al-zor islamic state last major foothold syria syrian troop iran-backed militias close west since last week sdf advance east russian u.s. battle islamic state syria mostly stay way euphrates often act divide line talk way extend formal demarcation line officials say u.s. coalition say sdf plan enter deir al-zor city syrian soldier break islamic state siege last since 2014. still june sdf accuse syrian military bomb position raqqa province unite state shoot government warplane syria crowd airspace ahmed abu khawla commander sdf deir al-zor military council say russian syrian fighter jet fly government territory dawn saturday warplanes strike sdf wag heat bloody battle industrial zone eastern bank seize factories islamic state militants say request explanations russian government tell reuters ask explanations coalition ... necessary action stop jet air raid come day khawla say fighters would let syrian government force cross euphrates friday warn army ally fire across river say do recent days russian foreign ministry say units syrian army already cross senior aide president bashar al-assad say government would fight force include u.s.-backed fighters recapture entire country say happen tomorrow ... strategic intent bouthaina shaaban say tv interview syrian troop ally force capture villages western bank euphrates saturday state media say shi ite militias fight damascus also launch attack islamic state south deir al-zor province along border frontier inside iraq military say iraqi arm force dislodge islamic state natural gas-rich akashat region caliphate islamic state say 2014 establish span countries effectively collapse july iraqi offensive capture city mosul syria militants lose much headquarter raqqa sdf help air strike special force u.s.-led coalition jet strike u.s.-backed force eastern syria