CAIRO (AP) -- In Egypt's bloodiest day since the Arab Spring began, riot police Wednesday smashed two protest camps of supporters of the deposed Islamist president, touching off street violence that officials said killed nearly 300 people and forced the military-backed interim leaders to impose a state of emergency and curfew.
The crackdown drew widespread condemnation from the Muslim world and the West, including the U.S., and Nobel Peace Prize winner Mohamed ElBaradei resigned as the interim vice president in protest -- a blow to the new leadership's credibility with the pro-reform movement.
"Today was a difficult day," interim Prime Minister Hazem el-Beblawi said in a televised address to the nation. While he regretted the bloodshed, he offered no apologies for moving against the supporters of ousted President Mohammed Morsi, saying they were given ample warnings to leave and he had tried foreign mediation efforts.
The leaders of Morsi's Muslim Brotherhood called it a "massacre." Several of them were detained as police swept through the two sit-in sites, scores of other Islamists were taken into custody, and the future of the once-banned movement was uncertain.
Backed by helicopters, police fired tear gas and used armored bulldozers to plow into the barricades at the two protest camps in different sections of Cairo where the Morsi supporters had been camped since before he was ousted by the military July 3.
Army troops did not take part in the two operations, which began shortly after 7 a.m. (0500 GMT -- 1 a.m. EDT), although they provided security at the locations.
The smaller camp -- near Cairo University in Giza -- was cleared of protesters relatively quickly, most taking refuge in the nearby Orman botanical gardens, on the campus of Cairo University and the zoo.
But it took about 12 hours for police to take control of the main sit-in site near the Rabaah al-Adawiya Mosque in Nasr City that has served as the epicenter of the pro-Morsi campaign and had drawn chanting throngs of men, women and children only days earlier.
After the police moved on the camps, street battles broke out in Cairo and other cities across Egypt. Government buildings and police stations were attacked, roads were blocked, and Christian churches were torched, Interior Minister Mohammed Ibrahim said.
At one point, protesters trapped a police Humvee on an overpass near the Nasr City camp and pushed it off, according to images posted on social networking sites that showed an injured policeman on the ground below, near a pool of blood and the overturned vehicle.
The Health Ministry said 235 civilians were killed and more than 2,000 injured, while Ibrahim said 43 policemen died in the violence. The death toll was expected to rise.
Three journalists were among the dead: Mick Deane, 61, a cameraman for British broadcaster Sky News; Habiba Ahmed Abd Elaziz, 26, a reporter for the Gulf News, a state-backed newspaper in the United Arab Emirates; and Ahmed Abdel Gawad, who wrote for Egypt's state-run newspaper Al Akhbar. Deane and Elaziz were shot to death, their employers said, while the Egyptian Press Syndicate, a journalists' union, said it had no information on how Gawad was killed.
For much of the afternoon, thousands of Morsi supporters chanting "God is great!" tried to join those besieged by the security forces inside the Nasr City camp. They were driven away when police fired tear gas.
Smoke clogged the sky above Cairo and fires smoldered on the streets, which were lined with charred poles and tarps after several tents were burned.
The Great Pyramids just west of Cairo were closed to visitors for the day together with the Egyptian museum in the heart of the city. The Central Bank instructed commercial banks to close branches in areas affected by the chaos.
"Egypt has never witnessed such genocide," Brotherhood spokesman Ahmed Aref told The Associated Press from the larger of the two protest camps before it was cleared.
The pro-Morsi Anti-Coup alliance alleged security forces used live ammunition, but the Interior Ministry, which is in charge of the police, said its forces only used tear gas and that they came under fire from the camp.
Police dismantled the main stage near the mosque in the eastern Cairo district of Nasr City, the official MENA news agency said. An AP reporter saw hundreds of protesters leaving the sit-in site carrying their personal belongings.
"I already wrote my will and gave my wife the number of my bank account and told her who owes us money and who we owe money to," said 28-year-old chemist Ahmed Shaker during a brief break in fighting with security forces at the Nasr City camp.