Throughout most of German-occupied Europe, the Germans sought to round up and deport Jews to killing centers in occupied Poland. Some Jews survived by hiding or escaping from German-controlled Europe. Some escape routes out of occupied Europe led to belligerent states (such as the Soviet Union), neutral states (such as Switzerland, Spain, Sweden, and Turkey), and even to states allied with Germany (such as Italy and Hungary before they were occupied by Germany). After the German attack on the Soviet Union, more than a million Soviet Jews escaped eastward, fleeing the advancing German army. Thousands more Jews managed to leave Black Sea ports in Bulgaria and Romania, seeking to reach safety in Palestine.