Bayan jerin hare-hare hudu kan masana kimiyya a shekara ta 2010 zuwa 2012, an yi amanna cewa hukumar leken asiri ta Mossad a Isra'ila ce ta kaddamar da harin, an kuma zargi kawar Iran Hezbollah kan hannu da kai harin bam a kan wata motar safa makare da 'yan yawon bude idon kasar Isra'ila a Bulgaria cikin shekara ta 2012.
