The UN agency for Palestinian refugees, UNRWA, has issued an urgent plea for humanitarian access to the Yarmouk district in the south of the Syrian capital.

The neighbourhood, referred to as the Yarmouk camp since it is home to mostly Palestinian refugees, has been shelled intensely by government forces since the Islamic State of the Iraq and Levant (ISIL) launched an offensive against a Palestinian armed group there.

UNWRA said the situation in Yarmouk, where thousands of civilians have been trapped for weeks without receiving vital aid, was a "source of universal shame".

Some civilians were able to flee the area on Sunday, according to UNRWA. The agency said it had been able to provide life-saving humanitarian support to 94 civilians, including 43 women and 20 children, who fled Yarmouk.

Fighting has been raging since Wednesday between ISIL and rival armed groups. However, an activist in Yarmouk, speaking to Al Jazeera on condition of anonymity, told Al Jazeera that the government's bombardment of residential areas has been the main cause for civilian casualties and the humanitarian crisis.

'Barrel bombs'

According to the activist and the Syrian Observatory for Human Rights, a UK-based monitoring group, government helicopters have dropped barrel bombs, which are highly indiscriminate and destructive explosives, on the district. There were no details on casualties.

The Yarmouk activist said doctors and hospital staff were part of the group of people that managed to flee the district, further crippling its already deprived medical system. 

ISIL fights for control of Yarmouk

The activist also said that shortages of food and water have caused rampant hunger and suffering among civilians.

Palestinian officials in Damascus and other Syrian activists have said that ISIL seized control over up to 90 percent of Yarmouk and have been battling opposition groups across the district.

But the Yarmouk activist denied reports that ISIL took most of the district, saying the cause for the intrusion of the group - coming from the nearby district of Hajr al-Aswad - was not to seize territory there, but to punish the Palestinian faction Aknaf Bait al-Maqdis for arresting ISIL fighters accused of assassinating one of their leading figures.

Fighting between the two sides has continued mainly in the southwestern outskirts of Yarmouk.

Marwan Kabalan, a Syrian political analyst, told Al Jazeera that ISIL may be trying to expand its control in Damascus from the adjacent district Hajr al-Aswad, where it has been based for months.

But he also noted that it would probably be "too difficult to take control over all of Yarmouk" for several reasons, including its urban nature and the number of armed groups that have established their foothold there.

"It [Yarmouk] is quite a big area. It was once the most populated area in Damascus, and now there are many armed groups there," he said.

"The regime has failed to seize the district from rebels for more than two years."

Activists reported that reinforcements from rebel groups, including Jaish al-Islam, arrived in Yarmouk on Sunday and managed to recapture several areas from ISIL.

Besides ISIL, control over Yarmouk is divided between the armed opposition groups of Ahrar al-Sham, the Nusra Front, Free Syrian Army groups, and Aknaf Bait al-Maqdis.

The Syrian Observatory for Human Rights reported on Sunday that ISIL captured at least 10 fighters from Aknaf Bait al-Maqdis and other rebel groups.

Pro-ISIL media accounts published pictures showing 11 rebel fighters captured by ISIL besides some ammunition they seized.

Yarmouk was once a sprawling neighbourhood home to 160,000 Palestinian refugees and Syrians but has been caught up in the country's fighting and besieged by regime forces for more than a year.

About 18,000 residents are estimated to remain in the camp after many fled the fighting.

Ali Haidar, the Syrian minister of information, told Al Jazeera that the government had been working on a reconciliation deal under which the Palestinian factions would lay down their arms, and in return the government would end the siege.

"We were days away from an agreement. However, rebel groups who are not Palestinian are against reconciliation, like Nusra Front and Ahrar al-Sham. This is why these groups allowed ISIL to come into the camp," he said.

Source: Al Jazeera