More than 40 airstrikes hit opposition-held areas in Aleppo, Syria, Oct. 16, killing at least 49 people. (Aleppo Media Center via Storyful)

BEIRUT – The video captures what would be an extraordinary moment anywhere else in the world. But the footage purportedly comes from a rebel-held district of war-torn Aleppo, Syria, where almost unimaginable suffering and miraculous survival have become daily occurrences.

A boy is shown dangling from the upper level of an apartment building that apparently had just been hit by an airstrike. His legs appear crushed under concrete, trapping him in the bombed-out structure but somehow preventing a seemingly lethal fall to the ground. Emblazoned on his dust-covered shirt is this phrase: “Don’t Shoot.”

Incredibly, he survived, albeit dazed and holding on for dear life.

The footage – aired Sunday evening by pro-opposition media in Syria – is yet another reminder of the relentless brutality that is being inflicted on the roughly 250,000 people living in the opposition-held districts in the city’s east.

For weeks, pro-government forces, which control Aleppo’s west end, have been imposing a siege of the city’s rebel areas. And warplanes operated by President Bashar al-Assad’s government and Russia have intensified air raids there, too, systematically targeting homes, hospitals and infrastructure.

Peace efforts to stop the bloodshed – including a cease-fire brokered last month by the United States and Russia – have failed. Assad wants the rebels in what once was Syria’s largest city to surrender, but they are resisting.

Civilians, as a result, are dying in greater numbers as Aleppo becomes the most important battle in a civil war that has killed more than 400,000 people and turned millions of Syrians into refugees.

More than a dozen members of the same family were killed in an airstrike in eastern Aleppo on Monday, rescue workers said. In the past month, the Britain-based Syrian Observatory for Human Rights, a monitoring group, says the air raids on eastern Aleppo have killed 448 people, including 82 children.

The Aleppo Media Center did not identify the boy from Sunday’s video but said he is a resident of the city’s Qaterji neighborhood. The pro-opposition outlet blamed Russia – Assad’s most powerful ally – for the air raid, adding that the other people in the building died in the strike.

The footage shows a harrowing end to the boy's ordeal. Onlookers can be overheard shouting “God is great!” as a rescuer saves him.

Although the video’s authenticity couldn’t be independently verified, it highlights a situation that has been captured on camera seemingly countless times in the aftermath of attacks on eastern Aleppo. That includes pictures of Omran Daqneesh, 5, a boy from that area who was photographed in the back of an ambulance after barely surviving a pro-government air raid in August.

Like the boy from Sunday's video, Omran was in the Qaterji neighborhood at the time of the attack. Both may have lived to see another day, but they are likely to endure even more brutality as Syria’s civil war rages.

Zakaria Zakaria in Istanbul contributed to this report.