Activists say shelling and sporadic clashes are striking a Palestinian refugee camp in the Syrian capital, a situation a U.N. official describes as "beyond inhumane."

Hatem al-Dimashqi, an activist based in an area just south of Damascus, said the Yarmouk camp witnessed sporadic clashes and shelling Monday.

Chris Gunness, a spokesman for the U.N. agency that supports Palestinian refugees known as UNRWA, told The Associated Press in Barcelona late Sunday that the agency has not been able to send any food nor any convoys into the camp since the current round of fighting started.

Gunness said: "That means that there is no food, there is no water and there is very little medicine."

Islamic State militants stormed the camp Wednesday, marking the extremist group's deepest foray yet into Damascus.