russian military build bridge across euphrates river near deir al-zor move troop vehicles side support syrian army offensive russian tv report tuesday show footage truck move across bridge russian tv channel report military erect bridge fire islamist militants less 48 hours could also use deliver humanitarian aid evacuate sick wound 8,000 vehicles weigh 50 tonnes would able cross bridge 24 hour period include tank tv channel report say bridge locate east deir al-zor russia build bridge move troop across syria 's euphrates river tv