When the Syrian government launched its assault on Aleppo's rebel-held enclave of Salaheddin at dawn July 28, rebel fighter Abu Omar had no idea that he would soon make his first kill – as he put it – in the name of freedom.

As the sound of gunfire and exploding grenades began to cascade noisily outside, Abu Omar and a handful of rebels from the Free Syrian Army (FSA) leapt anxiously from their mattresses, donned fighting gear, and raced downstairs to step into the fight.

"I don't think the [Syrian] Army will come here. We killed it before," said Abu Omar as the battle commenced. Whatever the outcome, it would be a victory, he said. "If someone from the Free Army dies, we don't get sad. For sure they are in Paradise."

"We will not let the Syrian Army get into Salaheddin before we die," vowed a fighter named Malek.

The Battle of Aleppo may prove a pivotal point when the history is written of Syria's fateful civil war, which could bring to an end the Assad family's 42-year dynasty and change strategic balances across the Middle East. The result of the first two days of the assault, witnessed by the Monitor in the Salaheddin enclave, indicate that far more blood will be shed before either side can declare "victory."

Already the 17-month uprising has claimed upwards of 17,000 lives. Regime forces have fought back ferociously in Homs, Damascus, and in many other cities, leaving a trail of death and destruction that has shocked many Syrians and broadened hatred toward their ruler.

Yesterday, at the outset of a visit to the region, US Secretary of Defense Leon Panetta said of the Aleppo assault that "this kind of tragic attack ... ultimately will be a nail in Assad's coffin."

"What Assad has been doing to his own people ... makes clear that this regime is coming to an end," he said.

[Today, Syrian state TV claims the Army has taken "complete control" of Salaheddin from "mercenary forces." However, rebels disputed that claim, with a senior FSA commander for Aleppo telling Agence France-Presse that government forces had "not progressed one meter."]

Before battle, tanks amass

In recent weeks, rebels made gains in southwestern and eastern districts, and Aleppo held its breath as it waited for the inevitable counter-strike from the Syrian Army.

From dawn to dusk on July 27, helicopters circled overhead, firing constant bursts from heavy machine guns. Some 80 tanks arrived as reinforcements on the western side of the city.

The only questions were when the attack would come, how violent it would be – and whether the rebel FSA could stall a far superior military force.

On the street in Salaheddin after dawn on July 28, rebel fighters quickly loaded rocket-propelled grenades that had arrived overnight. Sacks of bullets were sent closer to the front, handfuls of them stuffed into pockets.

In one narrow entryway, a new green tin of fragmentation grenades sat on the ground, waiting for use and labeled in the American fashion, "8 Grenade Hand / High Explosive Offensive." A gray box without markings held more RPG rounds and a red plastic shopping sack was heavy with bullets.

As Syrian Army tanks began moving in from the north, Abu Omar was sent out to take part in a diversionary attack on a nearby military fuel point. He said later that when he arrived there, the fighters already had too few bullets, so they "failed" to seize the post.

But Abu Omar, a former special forces soldier who defected to the rebels, could see a government soldier hiding between some stones. He took up his position with his Austrian-made Steyr AUG assault rifle, its serial numbers ground off, like much of the new weaponry in the hands of the FSA, to hide the identity of the nation that provided it.

The rebels shouted a warning to the government soldier.

"I didn't want to shoot him. The FSA was saying, 'Surrender, surrender! We don't want to kill you!'" Abu Omar recalled. "But he still kept shooting, so I shot him and he went down."

Seeking reassurance in prayer

Back on the streets at the makeshift rebel base, fear grew as the sound of gunfire and explosions came closer, echoing among the multi-story apartment buildings and narrow roads, their criss-crossed electricity and phone wires and cloth-hung balconies reminiscent of the warrens of south Beirut.

With every new explosion, men and rebel fighters clustered in doorways quietly said "Allahu Akbar" ("God is the greatest"). They knew they were outgunned; that knowledge was etched in the fear evident on every face.

A louder chant went up at 8 a.m. and spread along the street: "Allahu Akbar! Allahu Akbar...." One older man with a long white beard began to pray aloud, mouthing lines from the Quran. Finally, his courage leaving him, he just whispered repeatedly, "Allahu Akbar, Allahu Akbar, Allahu Akbar...."

The shooting escalated further. Then the white-bearded man turned to an FSA officer and asked, almost choking: "Where's the Army?"

Within minutes, a rebel raced out onto the street with news: Five Syrian Army tanks had been destroyed. In that split second, despair gave way to relief and triumph, and the fighters lining the street raised their arms and shouted praise of God at the top of their lungs.

These were not jihadists, although some of those are on Syria's rebel frontline. On the streets of Salaheddin, they were proof of the old adage that there are no atheists in foxholes.

Barrage of artillery

Video footage seen by the Monitor shortly after the showdown bolstered rebel claims: It showed a Syrian armored vehicle with an RPG hole in its side still smoldering, and a number of Syrian soldiers lying dead at their positions on a wide avenue. Later footage showed burnt tanks.

The assault had been stopped, at least on the ground.

But shortly after came the roar of artillery barrages. Mortars, rockets, and tank shells were unleashed on the rebel enclave and did not end, nor even ease up, until well into the night.

Casualties began to pour in to the makeshift field hospital. Civilians said the intense shelling felt like regime revenge for the earlier military setbacks.

Few Syrians here forget the example of the rebel stronghold of Bab al-Amr in Homs – which was destroyed by weeks of artillery bombardment earlier this year, then declared "free" – or the more recent brutal "cleansing" of rebel turf in Damascus.

The bombardment was so intense that the United Nations estimates that in the last two days alone, 200,000 of the city’s 2 million residents have fled.

Artillery shells and rockets fell every few minutes in Salaheddin, sometimes as often as one a minute and sometimes in groups of five, coming in rapid succession. Some landed so close to the field hospital that shrapnel and debris hit the roof or walls.

Cars came through in a steady stream, screeching their wheels as they came around corners to announce and deliver casualties from the frontline. Wounded FSA soldiers, some with shrapnel but most with bullet wounds, were carried in on stretchers to be bandaged up, sewn up, or – in the case of one Palestinian "martyr" Musa Keilani – to be reverently left on the table for a moment and cried over.

'We are not terrorists, we are men.'

One middle-aged fighter was so angry about his head wound that, after it was sutured, he stood up, took the IV from his arm, and jumped into a car to return to the fight, declaring that he would find either "victory or dying."

Ambulances brought more and more civilian wounded as the day ground on. There were older men and women caught in their homes in the deluge of bombing, a boy bleeding from his trousers, and civilians pierced by snipers' bullets.

One medic stepped out of the treatment room with one hand colored red and shouted, disbelievingly, "This is civilian blood!"

"All the governments of the world are against the Syrian people," he exclaimed. "We are not terrorists, we are men."

An exhausted medical assistant sought to dispel the official line from Damascus that the uprising had been hijacked by Islamists. "This is not a religious revolution, it's a Syrian revolution," he said. "Some people have long beards, but they are good men, not terrorists. They believe in Syria."

One 120mm mortar shell landed less than a block from the field hospital, just as an older wounded man had been wheeled outside to be taken elsewhere. As the blast rocked the scene, he could only raise a hand slowly to shield his face. He was then wheeled back in, to wait for a gap in the shelling.

Outside, terrified families raced across streets looking for better shelter. Those who got to the makeshift hospital – some of them found and escorted by FSA soldiers tasked with protecting civilians – were visibly shaken by their ordeal, cradling children, sometimes weeping.

"We are here because from morning the Bashar al-Assad regime has burned and destroyed all things," screamed one woman, sitting in a room with three other families, waiting to be taken to safer place.

"We were running on the street while the bombs were falling," said one man. "The Free Syrian Army protected us, and brought us from our houses."

"The FSA will save us, and God save them!" shouted the woman, before launching into a loud prayer. Another family entered the room, looking shocked.

"There is no safe place in all of Syria; all the streets are under attack," said the first woman. Then, as a series of rockets impacted not too far away, she addressed the newly arrived family: "What you hear now is nothing! You should expect more."

The man came up to this reporter and pleaded: "Please let all our words be published."

Another family man made clear his view of Assad's aim, one that echoes repeatedly in this rebel stronghold: "He is trying to kill all the people."

Is time on the rebels' side?

After the first day of the government assault, Abu Omar – the rebel who killed a Syrian soldier early in the morning – was optimistic that time was on the rebel side, given the state of Syrian forces he left behind when he defected several months ago.

"When I was still in the regime army, sometimes we would go four days with no food or electricity, and that makes soldiers afraid and weak," he says. "But they have been an army for 40 years. We can't win this war just like this," he says, snapping his fingers.

Several days ago Abu Omar was contacted by a Syrian soldier from his old unit, one who had had enough. He and 10 others wanted help defecting. Two days ago that number jumped to 20.

More weapons arrive

Sitting on his mattress after midnight, as artillery shells still fell on the neighborhood – some close enough to break glass nearby – Abu Omar detailed the state of play.

The bombardment "shows [the Army is] weak and helpless; it shows they can't get into Salaheddin," he said. "More power is coming, more weapons, more guns."

Indeed, by the next morning the weapons store had been replenished with fresh crates of ammunition and an out-of-the-box Dushka-style heavy machine gun.

Get the Monitor Stories you care about delivered to your inbox. By signing up, you agree to our Privacy Policy

But on the sidewalk outside the Salaheddin field hospital was a body wrapped in a bloodied white shroud, waiting to be taken away – ironically under graffiti which read: "Our Free Army is our guardian, after God."

* Scott Peterson left the Salaheddin district of Aleppo late Sunday afternoon. Follow him on Twitter.