(Hebrew for “organization”) Also known as Etzel, which is the Hebrew acronym for “Irgun Tzvai-Leum” or "National Military Organization.” The Irgun was an underground Jewish paramilitary group active during the British mandate of Palestine. Considered a terrorist entity by the British administration and a radical rival by the dominant Labor Zionist movement, the Irgun undertook armed operations against both Palestinian Arab communities and the British. In 1946, Irgun members bombed the King David Hotel, which served as a British command post. On April 9, 1948, members of the Irgun were identified as participating in the attack on the Palestinian Arab village of Deir Yassin. The Irgun was completely dismantled and subsumed into the Israeli army by September of 1948. One of the Irgun’s main commanders was Menachem Begin, Prime Minister of Israel from 1977-1983. See Segev, Tom. One Palestine, Complete: Jews and Arabs Under the British Mandate. New York: Henry Holt and Company, 2000; and Morris, Benny. Righteous Victims: A History of the Zionist-Arab Conflict, 1881-2001. New York: Vintage Books, 2001.  http://www.justvision.org/glossary/irgun