. ▁N ine ▁people ▁were ▁killed , ▁of ▁whom ▁three ▁were ▁Indones ian , ▁three ▁were ▁Austral ians , ▁two ▁were ▁from ▁The ▁Netherlands , ▁and ▁one ▁was ▁from ▁New ▁Zealand . ▁More ▁than ▁ 5 0 ▁people ▁were ▁injured ▁in ▁the ▁bl asts . ▁Both ▁bl asts ▁were ▁caused ▁by ▁suic ide ▁bom bers , ▁who ▁checked ▁into ▁the ▁hot els ▁as ▁pay ing ▁guests ▁several ▁days ▁earlier . ▁The ▁tw in ▁suic ide ▁bomb ings ▁came ▁four ▁years ▁after ▁the ▁previous ▁serious ▁terror ist ▁attack ▁in ▁Indones ia . ▁ ▁Background ▁Since ▁the ▁ 2 0 0 2 ▁B ali ▁bomb ings , ▁in ▁which ▁ 2 0 2 ▁were ▁killed , ▁Indones ia ▁had ▁stepped ▁up ▁attempts ▁to ▁crack ▁down ▁on ▁terror ism . ▁An ▁anti - ter ror ism ▁law ▁was ▁confirmed ▁by ▁the ▁Indones ian ▁legisl ature ▁in ▁ 2 0 0 3 . ▁The ▁ 2 0 0 2 ▁attack ▁was ▁carried ▁out ▁by ▁J ema ah ▁Is l ami y ah , ▁a ▁group ▁previously ▁linked ▁to ▁al - Q a eda ▁and ▁later ▁to ▁Islam ic ▁State ▁of ▁Ira q ▁and ▁the ▁Lev ant , ▁and ▁seeking ▁to ▁un ite ▁Indones ia , ▁Malays ia , ▁and ▁the ▁southern ▁Philippines ▁as ▁an ▁Islam ic ▁state . ▁ ▁The ▁Mar ri ott ▁had ▁previously ▁been ▁the ▁target ▁of ▁a ▁suic ide ▁bomb ing ▁in ▁ 2 0 0 3 . ▁ ▁The ▁attacks ▁ ▁The ▁Mar ri ott ▁bomb ing ▁occurred ▁first ▁and ▁was ▁followed ▁five