Updated at 5:35 p.m. EDT

Islamic State militants and al-Qaida's Syrian affiliate appear to have worked together earlier this week to seize a Palestinian refugee camp on the outskirts of the Syrian capital.

The Syrian Observatory for Human Rights reports that ISIS and al-Nusra Front gained control of about 90 percent of the Yarmouk refugee camp after an assault on Wednesday. A Palestinian official says today that civilians were fleeing the camp amid clashes between the extremist groups and Palestinian armed factions.

NPR's Emily Harris tells our Newscast unit that Palestinian officials based in the West Bank are calling for safe passage to allow Palestinians to leave. "One official said they are caught in a conflict that is not theirs," Emily says: "Another said this highlights the need to find a permanent resolution for all displaced Palestinians."

The Associated Press quotes Khaled Abdul-Majid, a Damascus-based Palestinian official, as saying ISIS and al-Nusra fighters control only about half of the camp, which is located on the edge of the Syrian capital.

Voice of America reports:

"In addition to the ground clashes, United Nations officials said Syrian forces were shelling the camp. Violence during the past week has trapped its residents – about 18,000 civilians, including many children – inside the camp."The United States on Saturday condemned the attacks on Yarmouk. It said the actions of the Islamic State group and its allies are a "severe risk" to civilians who already have been under siege for two years, deprived of desperately needed food, medical supplies and other essentials."

The AP quotes an activist based in an area just south of Damascus, Hatem al-Dimashqi, as saying that "the rebel groups have launched a counteroffensive aimed at ousting the militants from the camp. He said a number of factions based inside the camp and in surrounding areas including Yalda, Babila and Beit Saham formed a joint operations command to coordinate their military action."

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