Clandestine immigration was the spur to and a focal issue of the resistance to the "White Paper" policy of the British mandatory regime in Palestine.
The Mossad organized large-scale operations at sea. Immigrants, mainly refugee survivors of European Jewry, embarked at small, remote
ports and traveled under cramped conditions in densely packed vessels from Italy to
Eretz Yisrael. Many were arrested by the British Coastguard, and deported to Cyprus detention
camps.
The struggle reached its peak in July 1947, when 4,515 refugees on board the
Hagana ship Exodus reached the shores of Palestine. After a fight on board with the
British, when 3 were killed and 28 injured, the
passengers were transferred against their will from the Exodus to British
deportation boats and to a British internment camp in Germany.
This incident aroused world opinion against Britain's policy of closing the gates of
Palestine to survivors of the Holocaust. The Exodus became the symbol of the clandestine immigration operations.