amman military jet believe russian kill least 60 civilians try flee heavy fight oil rich deir al zor province syria small boat target seek cross euphrates river opposition activists former residents war monitor say late wednesday say jet target makeshift rubber dinghies boat carry dozens families flee town al ashara along western bank euphrates lie south deir al zor city provincial capital islamic state last major stronghold cities towns farm fertile strip along euphrates border iraq fast become focus syria six-year-long civil war russian jet stag second wave strike boat flee across river cause casualties among rush rescue early survivors say abdullah al akaidat tribal figure northern syria al ashara contact relatives area russia throw military weight behind syrian army campaign regain province border iraq race u.s- back force grab territory islamic state u.s. coalition jet last year destroy bridge link villages northeast euphrates river towns opposite bank although goal cut militant supply line force people use ferry cross river tributaries rupture major lifeline civilians raise price goods food fifteen civilians kill air strike last 24 hours town al quriya north town ashara along river say former residents touch relatives thousands residents eastern province flee war-torn zone safety towns escape relatively unscathed relentless fight russians build bridge across euphrates near deir zor city move troop equipment militants wag surprise counter offensive claim kill dozens syrian troop russian grind troop iranian-backed fighters regain territory back islamic state release video tuesday two injure men claim russian soldier capture deir al zor province reuters could verify authenticity tape syrian army seek advance toward mayadeen city province 44 km southeast deir zor river flow mayadeen major islamic state stronghold also target u.s.-led coalition early year also increase bomb group cities towns along euphrates valley relentless airstrikes russian jet deir al zor province intensify recent days accord syrian observatory human right war monitor document death least 185 civilians include least 45 woman children five days aerial strike russia reject opposition human right group accusations bomb campaign kill thousands civilians since major intervention two years ago turn tide favor syrian president bashar al-assad score hospitals civil defense center bomb opposition say scorch earth policy paralyze life rebel-held areas moscow say attack hardline islamists syrian opposition say russian jet kill civilians flee across euphrates