The Palestinian terror group Black September had hijacked the craft and separated passengers into groups of Jews and non-Jews. They declared that they would blow up the plane if Israel did not release hundreds of Palestinians serving prison terms for charges of terrorism. The Palestinian terror group Black September had hijacked the craft and separated passengers into groups of Jews and non-Jews. They declared that they would blow up the plane if Israel did not release hundreds of Palestinians serving prison terms for charges of terrorism. The Palestinian terror group Black September had hijacked the craft and separated passengers into groups of Jews and non-Jews. They declared that they would blow up the plane if Israel did not release hundreds of Palestinians serving prison terms for charges of terrorism. The Palestinian terror group Black September had hijacked the craft and separated passengers into groups of Jews and non-Jews. They declared that they would blow up the plane if Israel did not release hundreds of Palestinians serving prison terms for charges of terrorism.