▁property , ▁fre ed ▁Lith uan ian ▁prisoners ▁and , ▁according ▁to ▁Ma ńcz uk , ▁executed ▁several ▁of ▁the ▁P MO ▁f igh ters ▁they ▁found ▁wounded . ▁ ▁On ▁the ▁evening ▁of ▁August ▁ 2 5 , ▁the ▁first ▁regular ▁unit ▁( 4 1 st ▁Infantry ▁Regiment ) ▁of ▁the ▁Polish ▁Army ▁received ▁an ▁order ▁to ▁advance ▁towards ▁Se j ny . ▁The ▁Lith uan ian ▁forces ▁retre ated ▁on ▁the ▁same ▁day ▁when ▁they ▁learned ▁about ▁the ▁approaching ▁Polish ▁rein for c ements . ▁According ▁to ▁Ma ńcz uk , ▁they ▁based ▁their ▁retre at ▁on ▁an ▁err one ous ▁report ▁about ▁a ▁" large ▁Polish ▁caval ry ▁unit " ▁operating ▁to ▁their ▁rear ; ▁only ▁small ▁groups ▁of ▁Polish ▁part is ans ▁operated ▁there . ▁Later ▁the ▁next ▁day , ▁during ▁the ▁afternoon ▁of ▁August ▁ 2 6 , ▁the ▁P MO ▁forces ▁in ▁Se j ny ▁were ▁joined ▁by ▁the ▁ 4 1 st ▁Infantry ▁Regiment . ▁ ▁On ▁August ▁ 2 6 , ▁a ▁large ▁anti - Pol ish ▁protest ▁took ▁place ▁in ▁Laz d ij ai , ▁with ▁c ries ▁to ▁march ▁on ▁Se j ny . ▁The ▁last ▁Lith uan ian ▁attempt ▁to ▁re take ▁the ▁town ▁was ▁made ▁on ▁August ▁ 2 8 . ▁The ▁Lith u ani ans ▁( about ▁ 6 5 0 ▁men ) ▁were ▁defeated ▁by ▁the ▁combined ▁forces ▁of ▁the ▁Polish ▁Army ▁( 8 0 0 ▁men ) ▁and ▁P MO ▁volunte ers ▁( 5 0 0 ▁men ).