The Palestinian refugee crisis in Syria, in a single photo

This picture taken on Jan. 31, 2014, and released by the United Nations Relief and Works Agency for Palestine Refugees in the Near East (UNRWA), shows residents of the besieged Palestinian camp of Yarmouk, queuing to receive food supplies, in Damascus, Syria. A United Nations official is calling on warring sides in Syria to allow aid workers to resume distribution of food and medicine in a besieged Palestinian district of Damascus. The call comes as U.N. Secretary General Ban Ki-Moon urged Syrian government to authorize more humanitarian staff to work inside the country, devastated by its 3-year-old conflict. (AP Photo/UNRWA)

A top United Nations official renewed demands to allow medicine and food to be distributed without restrictions inside an unofficial refugee camp in Damascus, Syria, where as many as 18,000 Palestinian refugees have been trapped since July, besieged by the country's 3-year-old civil war.

"I am deeply disturbed and shaken by what I observed today," Filippo Grandi, commissioner-general for the U.N. Relief and Works Agency, said in a statement from Beirut after returning from Yarmouk Camp, a suburb of Damascus eight miles south of its center. "The Palestine refugees with whom I spoke were traumatized by what they have lived through, and many were in evident need of immediate support, particularly food and medical treatment."

Refugees are experiencing "acute and widespread deprivation, including severe malnutrition," Grandi said. At least 100, including children, have died.

Yarmouk was built as a Palestinian refuge in 1948 during the Arab-Israeli war. Over the years, its population grew to 180,000, the largest settlement of Palestinians in Syria. U.N. officials estimate at least 140,000 were forced to flee their homes in Yarmouk as the Syrian conflict began in March 2011.

Those who remained became trapped by fighting between Syrian rebels and government forces. A precarious deal to allow humanitarian aid into Yarmouk, brokered among various Palestinian factions loyal to the government, and the rebels, resulted in only sporadic supplies of food and medicine.

Partial humanitarian access to the camp was granted last month, but earlier in February, fighting broke out, and access was suspended. Grandi visited the camp on Saturday, when humanitarian aid resumed.

“We hope that the positive developments in Yarmouk can give momentum to peaceful dialogue between all parties so that there can be humanitarian access for all civilians in Syria, who have suffered enough,” he said.

A photo, taken Jan. 31 and released recently by Grandi's agency, shows hundreds of refugees flooding the besieged camp, awaiting supplies.

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