Opposition activists said the rebel fighters entered the Syrian capital of Damascus at dawn Sunday, according to the Britain-based war monitor Syrian Observatory for Human Rights.

The monitor said hundreds of government soldiers were ordered to withdraw from Damascus International Airport, and were seen removing their military uniforms and donning civilian clothing.

Multiple media outlets have reported that Syrian President Bashar al-Assad has left the country, citing rebel forces. The Syrian presidency said Saturday al-Assad was still performing his constitutional duties in the capital.

Xinhua reporters in Damascus witnessed intense gunshots reverberating through the streets with heavy traffic caused by cars departing the capital.

Syrian Prime Minister Mohammad Ghazi Jalali said in a speech published on Facebook shortly after the rebels' claim of entering Damascus that he was ready to "cooperate" with any leadership chosen by the people and urged citizens against vandalizing public facilities.

Abu Mohammad al-Julani, leader of the Hayat Tahrir al-Sham (HTS) rebel group, has prohibited his forces from approaching public institutions, stating that they will remain under the supervision of the country's prime minister until they are officially handed over, according to a statement published on the group's social media outlets.

He also banned his fighters from opening fire in the air.

Later on Sunday, opposition forces in Syria took over state television channels to announce what they described as the fall of Damascus and the end of al-Assad's government.

A man in military fatigues, flanked by armed fighters, read the statement on air, calling it "Statement No. 1." He claimed that rebel units had captured Damascus.