CAIRO - It was around 3:30 a.m. in Cairo on Monday morning and time for fajr, the first of the day's five Muslim prayers. In an hour and a half, the sun would rise. Now, it was still dark. On a wide boulevard running in front of the heavily guarded gates of the Republican Guard club, a few hundred protesters were entering the fourth day of a sit-in demanding the reinstatement of ousted President Mohamed Morsy. They had been waiting, sleeping in sparse shade through the hot days, believing their president was held inside the compound. On Monday morning, they formed into lines, their backs turned to the soldiers guarding the gate, and began to pray. Less than two thousand feet away, in a high-rise apartment on the other side of the sprawling club, Salah and his family awoke. They prepared for fajr. Then they heard gunshots. Salah rushed to the window, turned on his phone and began to film. The shots cracked through the pre-dawn darkness, followed by more -- a rapid series of single blasts that sounded like they came from rifles. There was distant and incoherent shouting. Something that look liked black smoke drifted upward, and then more shots. Down below, Inside the club, Salah watched soldiers throw on flak jackets, jump into vehicles and drive toward the commotion. "There is no God but God," he muttered in trepidation. On the streets in front of the club, something terrible was happening. How it began, too, is shrouded in darkness. But how it ended was clear: at least 51 dead protesters, a dead soldier and a dead policeman. It was the worst act of state violence since the 2011 uprising, a "massacre" that threatened to push the huge but temporarily defeated Muslim Brotherhood even further from reconciliation with a new government they view as completely illegitimate. The killing isn't random or individual or against thugs like before. The killing is systematic and programmed, instructed and ordered by the military," Mohamed el-Beltagy, a leading member of the Brotherhood's Freedom and Justice Party, told reporters later on Monday. This is a crime that threatens all Egyptians, that this is the regime that awaits Egypt if they allow the continuation of this military coup. The two narratives of what occurred on Monday morning are as polarized as Egypt's politics, where belief now seems to hinge on affiliation over logic. The Brotherhood, castigated by many as an insular, clannish and reactionary religious militia, find themselves out of power and bereft of non-Islamist allies. They're framed by popular, privately-owned media as thuggish criminals undeserving of sympathy -- even in death. "Against terrorism," reads a banner permanently appended to the on-screen broadcast of the CBC network, unsubtly aimed at the Brotherhood. The military offered up its own press conference on Monday afternoon to explain why 51 citizens lay dead in the street. The spokesman said Morsy's supporters had attempted to storm the guards' compound using shotguns and Molotov cocktails. Others threw rocks and debris on the guards from above, he explained, and soldiers had no choice but to respond with lethal force. The story was problematic. Dozens of witnesses, including some not associated with the protesters, told reporters that violence began when soldiers and riot police fired tear gas to break up the sit-in and quickly began firing birdshot and bullets. Those who had been praying said the attack began suddenly, without provocation. Various survivors gave consistent statements. Doctors and journalists said the majority of the fatal gunshot wounds struck their victims from behind, as if they had been praying or fleeing. The military failed to produce any photographs or videos showing the initial alleged attack. The few they did provide showed two Morsy supporters responding later, during street battles after sunrise, with homemade pistols. The New York Times reported that the policeman who died was a local officer who had likely been shot by the military while hiding in his car, as they fired at protesters. There was clear evidence that soldiers had pursued the protesters far beyond the sit-in. By midday, troops had erected a barbed-wire barricade some thousand feet up a road leading to the primary pro-Morsy protest at the Rabaa el-Adaweya Mosque. Far beyond the barricade, protesters showed reporters blood stains on the street. A car and food kiosk in a nearby intersection were both pocked with bullet holes, as were lamp posts even farther up the road. Video circulated by the Freedom and Justice Party showed a police officer, in daylight, firing a shotgun at protesters as military riot police with batons advanced, as well as what appeared to be a soldier atop a nearby Defense Ministry building firing shots from an assault rifle down at the crowd. Mostafa Sharawy, a doctor who had arrived shortly after 5 a.m. to assist in a field hospital, said he had only come in time to see one casualty -- a man shot in the back. A bespectacled, thickly bearded young man who gave his name only as Mustafa and whose t-shirt and pants were covered in dried blood said he had been at the prayer, participating peacefully, when the sit-in was attacked. But the bloodshed seemed to sway few opinions in an environment where both sides have become unbending and entrenched. After citing a raft of problems they faced securing the country after the 2011 uprising, neither the military or Interior Ministry's spokesmen mentioned how many of Morsy's supporters had been killed or wounded on Monday. (According to the Health Ministry, at least 51 died and more than 300 were wounded. The Brotherhood claimed the death count had reached 70.) No member of the Egyptian press corps challenged the military's narrative of the violence. When he adjourned the press conference, he was applauded. On Monday afternoon, in a side street near the ongoing face-off between Morsy supporters and the military, a lawyer who gave him name only as Mahmoud and said he worked in the neighborhood watched as an eighth-floor office was slowly eaten by flames. Protesters claimed thugs had set it alight after seeing military personnel filming or firing from its windows. Other video suggested that Morsy supporters may have taken a position on top of the building, raising the possibility that a tear gas canister had started the fire. As Mahmoud looked on, four employees of the company that occupied the office space sat on a bench, observing the fire forlornly. Mahmoud said he felt no sadness for the dozens of Morsy supporters who had died that morning. They started this. I wish the army would come and clear them all out," he said. Mahmoud claimed that a friend who lived in a nearby street overlooking the Rabaa el-Adaweya sit in had seen a minibus full of weapons being stockpiled by the Brotherhood. He didn't have a picture to support the claim. They came and attacked the military with shotguns and Molotovs. What do you expect the army to do? They responded with automatic weapons," Mahmoud said. They wanted to provoke a response. The only thing they have left is international sympathy.