Irgun Cvai Leumi (National Military Organization) was a zionist militant organization and arguably even a terrorist group, which fought for the creation of a Jewish state in Palestine. Israelis often refered to Irgun as "Etzel." The movement was formed in 1931, on Palestinian territory. According to most sources, Irgun organized terrorist attacks against both the Arabs and the British occupiers.

One of the largest of attacks perpetrated by Irgun was the bombing of Jerusalem's King David Hotel in 1946. The hotel served as the headquarters of the British army's upper brass. In total, 91 people were killed in the blast, included 29 British citizens. Some of Irgun's terrorists were captured by British forces and several were tried and executed. As a form of revenge, Irgun captured two British soldiers and killed them, leading to an end to executions by British tribunals. Irgun also killed more than 250 Arabs during various attacks and conflicts between 1937 and 1939.

The group was disbanded in 1948.