Updated Tuesday, December 18, 2012 at 06:03 AM
Clashes between Syrian rebels and an armed Palestinian group loyal to President Bashar Assad raged inside a Damascus refugee camp Tuesday as opposition fighters pushed deeper into the capital, activists said.
The rebels fighting to topple Assad's regime have made significant tactical advances in the past weeks, capturing air bases and military installations in and around Damascus.
Their offensive in the Palestinian refugee camp of Yarmouk in southern Damascus, which began Friday, is aimed at driving the pro-government Palestinian gunmen out of the camp, which would be another blow to Assad and his loyalists.
When the revolt against Assad's rule began in March 2011, the half-million-strong Palestinian community in Syria tried to stay on the sidelines of the conflict.
But as the civil war deepened, most Palestinians backed the rebels, though some groups - such as the Popular Front for the Liberation of Palestine-General Command - have been fighting on the government side.
The Britain-based Syrian Observatory for Human Rights said the violence in Yarmouk is forcing an exodus of Palestinian refugees and Syrians who came to the camp in past weeks to escape violence elsewhere in the city. The Observatory relies on reports from activists on the ground.
Camp residents said several mortar rounds landed inside Yarmouk on Tuesday and gunfire has echoed around the area. The residents spoke on condition of anonymity, fearing for their safety.
They said there were no Syrian government troops in the camp and that most of the fighting was between rebels and gunmen from the PFLP-GC. The group is led by Ahmed Jibril, Assad's longtime ally.
Syrian pro-government Al Watan newspaper said Tuesday the army could be preparing an operation "to cleanse the Yarmouk camp of gunmen."
On Monday, Syrian Foreign Minister Walid al-Moallem claimed the clashes at the camp were triggered by the al-Qaida-linked Jabhat al-Nusra group, which was designated by the Obama administration a terrorist organization last week.
Al-Moallem warned Palestinians inside the camp not to harbor terrorist fighters.
The U.N. Relief and Works Agency for Palestine Refugees in Syria said it was "gravely concerned" for the Palestinian refugees in Yarmouk who "have experienced particularly intense armed engagements involving the use of heavy weapons and aircraft," UNRWA said in a statement.
There are also "waves of significant displacement" as about 150,000 Palestinian refugees in Yarmouk and thousands of Syrian residents of the camp "scramble to seek safety amid continued fighting," the agency said.
UNRWA is now housing over 2,600 displaced persons in its facilities and Damascus area schools, and the number is growing rapidly, the agency also said in a statement that was posted on its website late Monday.
Hundreds of Palestinians refugees from Yarmouk have also sought safety in neighboring Lebanon in the past days, according to UNRWA.
There were no immediate reports of casualties from Tuesday's fighting. At least eight people were killed in an airstrike on Yarmouk on Sunday, according to Syrian activists.
U.S. State Department spokesperson Victoria Nuland said Monday the United States is "deeply concerned" by reports that dozens of civilians were killed or wounded in Yarmouk as a result of aerial bombardment and fighting.
The U.N. humanitarian chief, Valerie Amos, who was just in Damascus meanwhile warned of a growing humanitarian crisis in Syria.
The 21-month battle to bring down the Assad regime has already forced some 3 million Syrians from their homes, according to a new estimate, and cold, wet winter weather is making life increasingly unbearable for the displaced. Among those who left their homes are more than 500,000 who fled to neighboring countries like Turkey, Lebanon and Jordan.
Amos told reporters Monday after briefing the U.N. Security Council on her trip that she asked the Syrian government to allow the U.N. to import fuel so the organization can move around Syria, and to allow 10 additional international humanitarian groups to work in the country to scale-up the U.N.'s work.
In related developments, Russia's Foreign Ministry said Tuesday that two Russians were kidnapped alongside an Italian in Syria and that their captors have asked for a ransom for their release.
The three, who worked at a Syrian steel plant, were kidnapped late Monday on the road between Tartus, where Russia has a naval base, and Homs, the ministry said in a web-posted statement. It did not specify the amount.
The kidnapping of foreigners has been rare, but as Syria descends further into chaos the abduction of Syrians has become increasingly common across many parts of the country.
Most of those kidnappings appear to have sectarian motives, part of tit-for-tat attacks between rebels and pro-regime gunmen. But there have been many cases of gunmen capturing wealthy people for ransom or settling personal scores.
Russia has been the key international ally of Syrian President Bashar Assad whose embattled regime is fighting rebel forces since March 2010 in a civil war that killed an estimated 40,000 people.
Associated Press writer Albert Aji in Damascus, Syria, contributed to this report.