The "Pan Crescent" and "Pan York" (renamed Atzma'ut and Komeimiut) were the two largest ships in the history of illegal immigration to Palestine.
Purchased in the United States in the spring of 1947, the "pans" were used to transport some 15,000 illegal immigrants from the port of Constanza in Romania to pre-State Israel. An agreement was reached with the Romanian government, and organization of the future immigrants was underway.
The British tried to prevent the ships from reaching the Black Sea. Sabotage was discovered on the Pan Crescent while in the port of Venice for outfitting, but both ships arrived at Constanza. Meanwhile, the British exerted heavy pressure on the governments of the U.S. and Romania. The US even threatened not to support the partition plan if the Jewish Agency Executive let the "pans" sail, and Romania reneged on its agreement to allow the ships to sail from Constanza.
The "pans" finally left the port of Burgas in Bulgaria on December 27, 1947, only after an agreement had been reached with the British that the ships would sail directly to Cyprus instead of Palestine, and that the "immigrants" would be interned there. The ships reached Cyprus on December 31, 1947.