The Polish resistance movement in World War II, with the Polish Home Army at its forefront, was the largest underground resistance movement in all of occupied Europe, covering both German and Soviet zones of occupation. The Polish resistance is most notable for disrupting German supply lines to the Eastern Front (damaging or destroying 1/8 of all rail transports), providing intelligence reports to the British intelligence agencies (providing 43% of all reports from occupied Europe), and for saving more Jewish lives in the Holocaust than any other Western Allied organization or government. It was a part of the Polish Underground State.