In a case that strikes at the heart of Israel’s national identity, South Africa formally accused the country of committing genocide against Palestinians and pleaded Thursday with the United Nations’ top court to order an immediate halt to Israeli military operations in Gaza.

Israel, which was founded in the aftermath of the Holocaust, has vehemently denied the allegations. As a sign of how seriously they regard the case, Israeli leaders have taken the rare step of engaging with the court to defend their international reputation. Israel often boycotts international tribunals or U.N. investigations, saying they are unfair and biased.