th ▁French ▁Col onial ▁Infantry ▁Division , ▁which ▁was ▁neighbor ing ▁the ▁Italian ▁ 3 5 th ▁Division ▁to ▁its ▁east , ▁was ▁ordered ▁to ▁attack ▁with ▁its ▁ 1 2 ▁batt al ions ▁the ▁positions ▁of ▁the ▁Bulgar ian ▁ 3 / 7 ▁Infantry ▁Brigade ▁and ▁parts ▁of ▁the ▁German ▁ 2 0 1 st ▁Infantry ▁Brigade ▁( 6 ▁Bulgar ian ▁and ▁German ▁batt al ions ▁in ▁total ). ▁The ▁art illery ▁prepar ation ▁for ▁the ▁attack ▁began ▁at ▁ 4 : 3 0 ▁and ▁pe aked ▁in ▁intensity ▁about ▁an ▁hour ▁later . ▁The ▁Al lied ▁bomb ard ment ▁destroyed ▁many ▁of ▁the ▁Bulgar ian ▁forward ▁inf antry ▁observation ▁posts , ▁caused ▁damage ▁to ▁the ▁fort ifications ▁and ▁covered ▁the ▁three ▁hills , ▁that ▁were ▁the ▁object ives ▁of ▁the ▁attack , ▁in ▁a ▁dense ▁cloud ▁of ▁smoke ▁and ▁dust . ▁At ▁ 6 : 3 0 ▁the ▁French ▁inf antry ▁advanced ▁with ▁three ▁reg iments ▁in ▁the ▁first ▁line ▁and ▁one ▁regiment ▁in ▁reserve . ▁ ▁On ▁the ▁right ▁the ▁ 8 th ▁Col onial ▁Infantry ▁Regiment ▁assault ed ▁the ▁hill ▁" D al ag ▁Gre ben " ( its ▁French ▁design ation ▁was ▁Pit on ▁Ro che aux ) ▁and ▁in fil tr ated ▁the ▁tren ches ▁def ended ▁by ▁two ▁batt alion ▁of ▁the ▁German ▁ 2 0 1 st ▁Infantry ▁Brigade . ▁Following ▁a ▁cost ly ▁hand - to - hand ▁eng agement ▁however ▁the ▁French ▁were ▁driven ▁out ▁which ▁left ▁the ▁fl ank ▁of ▁the ▁attack