▁cons olid ate ▁By z antine ▁control ▁of ▁the ▁northern ▁B alk ans . ▁Con sequently , ▁Di ogen es ▁invited ▁S erm on ▁to ▁a ▁meeting ▁at ▁the ▁est u ary ▁of ▁the ▁river ▁S ava ▁in ▁the ▁Dan ube , ▁where ▁each ▁would ▁only ▁be ▁accompanied ▁by ▁three ▁attend ants . ▁Di ogen es ▁had ▁hidden ▁his ▁sword ▁in ▁the ▁fol ds ▁of ▁his ▁clothes , ▁and ▁struck ▁S erm on ▁down . ▁He ▁then ▁march ed ▁his ▁army ▁into ▁S irm ium , ▁taking ▁possession ▁of ▁the ▁town . ▁S erm on ' s ▁wife ▁was ▁sent ▁as ▁a ▁capt ive ▁to ▁Constantin ople . ▁ ▁Ar ound ▁ 1 0 2 2 ▁or ▁ 1 0 2 5 , ▁Di ogen es ▁succeeded ▁A rian ites ▁as ▁overall ▁By z antine ▁commander ▁( str ateg os ▁aut ok r ator ) ▁of ▁conquer ed ▁Bulg aria . ▁In ▁this ▁capacity , ▁he ▁rep elled ▁a ▁large ▁Pe chen eg ▁invasion ▁in ▁ 1 0 2 7 . ▁The ▁same ▁year , ▁he ▁was ▁with dra wn ▁south ▁to ▁Th ess al onica ▁but ▁retained , ▁at ▁least ▁nomin ally , ▁his ▁role ▁as ▁overall ▁commander , ▁as ▁att ested ▁by ▁another ▁se al ▁naming ▁him ▁" anth yp atos , ▁patri ki os ▁and ▁dou x ▁of ▁Th ess al onica , ▁Bulg aria ▁and ▁Ser bia ". ▁ ▁Di ogen es ▁had ▁been ▁married ▁to ▁an ▁anonymous ▁daughter ▁of ▁Bas il ▁Ar gy ros , ▁brother ▁of ▁Emperor