U.N. High Commissioner for Human Rights Navi Pillay said attempts to deliver supplies to the 18,000 remaining in the camp in the suburbs of Damascus have repeatedly been thwarted since September 2013.
Over 160,000 Palestinian refugees lived in the town of Yarmouk until December 2012 when the majority fled after armed opposition groups entered the camp and government forces attacked, a U.N. statement said.
"Civilians, including many women and children, are caught in a quagmire between besieging Syrian government forces and affiliated militias surrounding the Yarmouk camp, as well as anti-government armed groups operating inside," Pillay said.
She added that intentionally directing attacks at those involved in humanitarian assistance is a war crime under the International Criminal court.
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