▁Bulg aria ) ▁and ▁Al ce k ▁( S ep ino , ▁Bo j ano , ▁I ser nia ). ▁In ▁the ▁Nom inal ia ▁the ▁Bez mer ▁( c . ▁ 6 6 5 – 6 6 8 ) ▁was ▁the ▁last ▁D ulo ▁r uler ▁on ▁the ▁Northern ▁side ▁of ▁Dan ube ▁river ▁( of ▁the ▁Old ▁Great ▁Bulg aria ), ▁while ▁the ▁As par uk h ▁( c . ▁ 6 8 1 – 7 0 1 ) ▁was ▁the ▁first ▁from ▁the ▁Southern ▁side ▁of ▁the ▁river ▁( First ▁Bulgar ian ▁Empire ). ▁He ▁was ▁followed ▁by ▁Ter vel ▁( c . ▁ 7 0 0 – 7 2 1 ), ▁and ▁the ▁last ▁r uler ▁of ▁Bulg aria ▁from ▁the ▁D ulo ▁cl an , ▁Se var ▁( c . ▁ 7 2 1 – 7 3 7 ). ▁According ▁to ▁The oph anes , ▁in ▁ 7 6 1 ▁or ▁ 7 6 2 ▁the ▁Bulg ars ▁" rose ▁up , ▁killed ▁their ▁her edit ary ▁l ords ▁and ▁set ▁up ▁as ▁their ▁king ▁an ▁evil - mind ed ▁man ▁called ▁Te let zes , ▁who ▁was ▁ 3 0 ▁years ▁old ". ▁Histor ians ▁usually ▁interpreted ▁the ▁testim ony ▁as ▁evidence ▁of ▁a ▁mass acre ▁of ▁the ▁previous ▁dynast y ▁( the ▁D ulo ▁cl an ), ▁and ▁the ▁rise ▁of ▁a ▁new ▁leader ▁with ▁no ▁connection ▁to ▁the ▁previous ▁regime . ▁ ▁Origin ▁The ▁exact ▁origin ▁is ▁obsc ure . ▁Some ▁research ers ▁consider ▁that