This year's commemoration is particularly noteworthy because of two recent high-profile deaths in prison that drew tremendous outcry from Palestinians. The Monitor explains.
The hunger strikers charge Israel with failing to provide adequate care for the man, who was diagnosed with cancer. Israel's Prison Service says it took him to a hospital and was arranging an early release.
Israel has released some details on the death in prison of Australian-Israeli Mossad agent Ben Zygier in a secret prison in 2010. But many questions remain unanswered.