Irgun (; shorthand for Ha'Irgun Ha'Tsvai Ha'Leumi B'Eretz Yisrael, , "National Military Organization in the Land of Israel") was a clandestine Zionist group that operated in Palestine from 1931 to 1948, as a militant offshoot of the earlier and larger Haganah (Hebrew: "The Defense", ההגנה) Jewish paramilitary organization.
The most well-known attack by Irgun was the bombing of King David Hotel in Jerusalem on 22 July 1946.