ALEXANDRIA, Egypt — As Muslim Brotherhood supporters rained stones and birdshot on demonstrators huddled at the opposite end of a busy street, Hamada Badr raced to the roof of a six-story apartment block to get a better view.
Some said 17-year-old Hamada and three teenage friends lobbed rocks at the pro-Brotherhood mob below. His friends denied this. But there is little dispute about what happened next.
Several Islamists chased after them, reached the roof and, to the horror of onlookers, threw three of the teens off the building in quick succession. Two fell 20 feet from a water tower to the main roof below and survived with injuries. A third escaped by clambering down a water pipe along the side of the building. But Hamada plummeted all the way to the ground, dying of severe internal bleeding at a hospital shortly afterward, friends said.
At least 17 people were killed Friday in Alexandria, Egypt's second-largest city, the highest reported death toll in a day of fiery protests nationwide against the military's removal of the controversial Islamist president, Mohamed Morsi. But it is the grisly circumstances of Hamada's death that have most stunned residents of this crumbling metropolis on the Mediterranean, prompting even onetime Morsi supporters to wonder whether the Muslim Brotherhood can ever regain political legitimacy.
"It was shocking," said Mustafa Said, a political activist with the liberal Constitution Party. "It makes you think the Brotherhood has gone crazy since Morsi's removal and doesn't know what it's doing."
Cellphone videos of the rooftop incident — though not showing Hamada's fall — surfaced Saturday and quickly became the most talked-about footage of the political unrest in Egypt. Anti-Morsi demonstrators returned to Field Marshal Ahmed Ismail Street on Sunday chanting, "Down with the murderers of children!"
Teenage boys, including Hamada's friends, sealed off the apartment building's black iron gate while murmuring bystanders snapped pictures of the rooftop.
This time, however, Egyptian soldiers aboard armored personnel carriers stood watch at the north end of the street, where Brotherhood demonstrators had begun their attacks two days earlier. Side streets were barricaded with concrete blocks and concertina wire and strewn with chunks of sidewalk that protesters had smashed up with axes to use as projectiles.
Long regarded as an Islamist stronghold — Egypt's ultraconservative Salafi movement was founded at a university here in the 1970s — Alexandria surprised many observers last year by backing a leftist candidate in the first round of presidential balloting. In the runoff election, voters chose Morsi over Ahmed Shafik, a longtime figure in the reviled government of Hosni Mubarak, but many residents turned on the Muslim Brotherhood leader within months.
In November, after Morsi issued a decree granting himself wide-ranging political powers, demonstrators burned down part of his party offices in Alexandria's bustling Sidi Gaber district, blocks from where the fighting raged Friday.
Mohamed Fawzi, 30, a barber who voted for Morsi, described the decree as "an act of political tyranny." Days later, five people were killed in violent clashes outside the presidential palace in Cairo. Fawzi said that convinced him that "Morsi was a murderer, not a president."
On June 28, the party offices in Alexandria were torched again in clashes that left two men dead, including an American college student. Morsi supporters responded with birdshot and Molotov cocktails, but that paled in comparison with the thousands of pro-Brotherhood demonstrators who poured into Sidi Gaber on Friday afternoon.
Friends described Hamada as a polite boy, a high school student who sang Egyptian pop songs and helped his father in a painting business. At first, he had watched the fighting from an alleyway. The first political act of his life might have been running to the rooftop, which led some Brotherhood demonstrators in the street below to think he was a sniper.
They waved weapons at him, demanding he come down, said Tamer Mohammed, who owns a supermarket across the street. Then a dozen Brotherhood demonstrators ran through the metal gate and to the roof.
Video shows Hamada and his friends cowering on a water tower as the Morsi supporters circle them, throwing rocks and sticks. They pull down Hamada, in a dark T-shirt, and begin beating him. Others climb up and shove two of Hamada's friends down to the roof, where they lie motionless as women's voices are heard shrieking.
The video cuts away before showing Hamada's fate. He fell down a narrow shaft in the building's interior. Friends said they found him collapsed on the ground floor, one arm nearly severed, blood everywhere.
"Hamada never had a fight with anyone," lamented Anwar Salah Hamdi, 20, whose younger brother Amir climbed down the side of the building.
The state news agency MENA reported Sunday that one man had been arrested in the incident.
Mahmoud Hashem, a Brotherhood member in Alexandria, blamed the violence on "hired thugs … who interfered to spoil the relationship between the Brotherhood and the people." He didn't specify who would have hired them.
The Badr home, a second-story apartment with blue shutters on a narrow lane of concrete tenements, was empty Sunday afternoon. Neighbors said Mohammed Badr, the father, was meeting with court officials. Reached by phone, Badr refused to speak to an American journalist, saying he "hates the U.S. administration" for supporting Morsi, whose partisans killed his only child.
Special correspondent Omar Halawa contributed to this report.