The Deir Yassin massacre took place on April 9, 1948, when Zionist paramilitaries attacked the village of Deir Yassin near Jerusalem, Mandatory Palestine, killing at least 107 Palestinian villagers, including women and children. The attack was conducted primarily by the Irgun and Lehi, who were supported by the Haganah and Palmach. The massacre was carried out despite the village having agreed to a non-aggression pact. It occurred during the 1947-1948 civil war and was a central component of the Nakba and the 1948 Palestinian expulsion and flight.

Deir Yassin was a Palestinian Arab village of around 600 inhabitants about 5 kilometers (3.1 mi) west of Jerusalem. Deir Yassin declared its neutrality during the 1948 Palestine war between Arabs and Jews. The village was razed after a massacre of around 107 of its Arab residents on April 9, 1948, by the Jewish paramilitary groups Irgun and Lehi. The village buildings are today part of the Kfar Shaul Mental Health Center, an Israeli public psychiatric hospital.