The Atlit detainee camp was a concentration camp established by the authorities of Mandatory Palestine in the late 1930s on what is now the Israeli coastal plain, 20 kilometres (12 mi) south of Haifa. Under British rule, it was primarily used to hold Jews and Arabs who were in administrative detention; it largely held Jewish immigrants who did not possess official entry permits. Tens of thousands of Jewish refugees were interned at the camp, which was surrounded by barbed wire and watchtowers.