AMMAN: The Syrian Arab Army (SAA) and its allies captured up to 20 percent of east Aleppo city on Monday, rebel military sources told Syria Direct, with an “unprecedented” barrage of airstrikes and artillery fire paving the way for the regime’s third consecutive day of advances.

Pro-regime forces captured the borderline district of a-Sakhour, that links what was the northern section of rebel-held east Aleppo with its more central districts to the south. As a-Sakhour was about to fall on Monday, hundreds of rebel fighters retreated to their territory to the south. A-Sakhour is one of roughly half a dozen districts that rebels lost.

The SAA’s Monday advances mark its largest single-day gains since the start of the intense Russian and Syrian regime campaign that began at the end of August to capture rebel-held east Aleppo.

 Airstrikes hit east Aleppo’s Bab a-Tariq district over the weekend. Photo courtesy of Mustafa a-Sarout.

“The advance happened quickly,” a rebel military source currently in east Aleppo told Syria Direct on Monday. “The scorched-earch policy spread the rebels out over a number of frontlines.”

“Regime forces have placed unprecedented pressure on the encircled neighborhoods by intensifying airstrikes,” said Mohammad Adeeb, a spokesman for the Nour e-Din a-Zinki faction currently fighting in east Aleppo.

Concurrent with the regime’s advances, Kurdish YPG forces—whom rebels have frequently bombed for several months in the district of Sheikh Maqsoud—capitalized on the reeling opposition by capturing two districts adjacent to their small Kurdish enclave inside Aleppo city. The land grab is the YPG’S first inside the provincial capital in more than a year.

At the time of publication on Monday, fierce clashes between rebel and regime forces were underway just south of the latter’s newly acquired territory.

“Right now, the situation can be described as nothing short of a desperate defense,” Abu al-Majd al-Halabi, a resident of east Aleppo’s al-Fardous district, told Syria Direct on Monday.

Why did an offensive regime campaign leaning heavily on thousands of airstrikes that began at the end of August make such a stunning turnaround just this past weekend? In the last five days, airstrikes have increased significantly with the apparent purpose of preparing the ground for a massive advance. Ultimately, the rebels were overwhelmed by the multiple fronts the regime opened on the ground.  

Rebel fighters on the frontlines attribute the defeat to an underlying shortage in manpower.

“We were spread so thin over a number of different fronts,” the rebel military source told Syria Direct on condition of anonymity. “We had no choice but to withdraw.”

Pro-regime forces launched more than 250 airstrikes and up to 6,000 artillery shells decimating opposition frontlines in the past 48 hours, sources in the Aleppo Civil Defense told Syria Direct on Monday.

“Calling this a humanitarian catastrophe can’t even do this situation justice,” Ibrahim al-Haj, spokesman for the Aleppo Civil Defense, told Syria Direct on Monday. “Words can’t express the full extent of the devastation caused by the regime’s massive escalation in bombing.”

 A Monday tweet from the Syria’s Defense Ministry: “Regaining complete control over the al-Halek district in east Aleppo.”

Pro-regime media widely celebrated the SAA advances, claiming rebel forces have lost as much as “45 percent of the territory they controlled last week,” Al-Masdar reported on Monday. “The jihadist rebels of Fatah Halab are crumbling inside the eastern pocket of Aleppo today, as they continue to lose district after district to the Syrian Arab Army and their allies.”

Drone footage filmed over recently captured regime territory shows entire city blocks leveled as a result of the SAA assault. Rebel sources told Syria Direct on Monday that Syrian and Russia “massively escalated” their air assault over the last five days.

Thousands of residents streamed out of the formerly rebel-held pocket in northeast Aleppo city for the second straight day on Monday amidst simultaneous SAA and YPG advances.

Estimates of the civilian displacement vary widely, with families fleeing either deeper into rebel-controlled east Aleppo or to regime and Kurdish areas on the city’s western side.

“Things are tough here, they’re getting worse every day and causing friction between people,” said east Aleppo resident al-Halabi.