dissertation on a hate-filled view of immigrant, immigration and muslims. unsigned. it is the killer's explanation for why he did this. >> these are people who i would describe as having extremist views that have absolutely no place in new zealand, and in fact, have no place in the world. >> reporter: the manifesto was posted online by this man, under the name brenton tarrant. cnn has not confirmed this is his real name but there is no doubt that the 28-year-old under arrest is a white supremacist who believe is his own white european race is being wiped out by immigration, labeling it white genocide. it is also the universal rallying cry of hate-filled white supremacists across the world. in charlottesville, virginia. the neo nazi cry was -- >> jews will die. >> in warsaw, poland, in 2017, some marchers in an independence day demonstration carried banners that read white europe and clean blood.