CAIRO // As many as 26 people were killed in Egypt yesterday as tens of thousands of supporters of Mohammed Morsi clashed with his opponents.
Alexandria saw the most deaths overnight as the Mena news agency reported at least 12 people killed during street battles between the rival groups.
Four supporters of the deposed president were killed near the a Republican Guard building in the Nasr City neighbourhood of Cairo early in the day.
The clashes on Cairo's 6th October Bridge came after the leader of the Muslim Brotherhood defiantly called on protesters to stay on the streets until a "military coup" was reversed.
"Our chests are stronger than bullets," said Mohamed Badie, the Islamist group's supreme guide. "Millions will remain in the squares until we carry our elected president, Mohammed Morsi, on our shoulders."
Mr Badie - who was earlier reported to be among the Brotherhood leaders arrested in a crackdown by the military after Mr Morsi was ousted from power on Wednesday - addressed thousands of the former president's supporters in Cairo after the pro-Morsi protesters were killed.
Hundreds were injured during demonstrations throughout in the day.
Mr Badie's fiery speech was met with huge cheers from the protesters. The presence of military aircraft, including helicopters hovering ominously over the demonstration and jet fighters soaring across the capital throughout the day, underscored the fraught mood left after the tumultuous events of the past week.
Egypt's biggest challenge in the coming days will be to calm a wave of anger from Brotherhood members and their Islamist allies, who adamantly believe the popular coup against Mr Morsi unseated the country's legitimate leader. As night fell yesterday, the huge crowds, chanting "betrayal, betrayal, betrayal", augured more confrontations.
Adly Al Mansour, who was sworn in as a transitional president on Thursday, vowed to include the Brotherhood in Egypt's political future. But officials from the group have called Mr Al Mansour's offer - and similar conciliatory messages from opposition politicians and the army - utterly hollow after army officers arrested top Brotherhood members and shut down their television stations this week.
Yesterday, Mr Al Mansour dissolved the country's interim parliament - the upper house of the legislature, which was overwhelmingly dominated by Islamists and Morsi allies.
Pro-Morsi protesters outside Cairo University said they would continue demonstrating until Brotherhood leaders were freed and the military ceased its interference in politics.
Mohamed Abdel Aziz, 37, an employee at the tourism ministry, said he would not take part in the new president's reconciliation initiative because there "is clearly no value to my vote".
"I'm here to point out the contradictions between the legitimacy that brought down Morsi and the legitimacy that brought him into office," he said. "Is it legitimate to close down television stations? Is it legitimate to limit freedom of speech? Is it legitimate to persecute media experts and elected politicians?"
Many said they attended to support Mr Morsi's "legitimacy", echoing the former president's last speech on Tuesday when he angrily called on Egyptians to refuse the military's interference in the democratic process.
The next day, the military, backed by religious leaders and opposition politicians, suspended the constitution and appointed an interim president. Mr Morsi was detained and has not been heard from since.
"I came to protect legitimacy and Islamic law," said Ismail Salam Eddin, a maths teacher from Cairo. The removal of Mr Morsi is "dividing the people and is a denial of democracy itself".
Eman El Alfy, 43, an English teacher outside Cairo University yesterday, called the military's move the beginning of a "war against Islam by traitors and agents".
"We won't leave our ground, our rights and our legitimacy," she said. "If you are injured in the service of God, you are happy."
Anti-Morsi protesters and politicians have described the military's harsh moves as necessary for Egypt's stability. Mohamed ElBaradei, the leader of the opposition National Salvation Front, told The New York Times on Thursday that the military had moved to prevent an "earthquake" in Egyptian society.
The arrests of Brotherhood leaders were "precautionary measures to avoid violence", he said, but added that nobody should be detained unless there were criminal charges against them.
The crackdowns have been met with criticism from human-rights groups.
"We fear that the violence of the last few days could spiral into a new wave of human-rights abuses," said Hassiba Hadj Sahraoui, the deputy director for the Middle East programme of Amnesty International. "It also resurrects fears of the army's abysmal record on human rights."
Egypt's public prosecutor yesterday ordered the release of two leading Brotherhood figures.
Saad El-Katatni, head of the Brotherhood's political wing and former speaker of parliament, and Rashad Al Bayoumi, one of the Brotherhood's deputy leaders had both been arrested on Thursday. They remain under investigation for inciting violence.
The military played an important role in the 2011 uprising against the regime of Hosni Mubarak. By refusing to clash with protesters and distancing themselves from the president, the top generals who make up the Supreme Council of the Armed Forces hastened Mubarak's exit.
But in the ensuing year and a half, that image was tarnished by its mishandling of Egypt's political transition and several incidents where troops fought with protesters, killing dozens.
There were also signs yesterday of escalating violence in the restive Sinai region, which shares a border with Israel. Two police officers were killed by unknown gunmen in the provincial capital of El Arish. Sinai has proved one of Egypt's most pressing security problems in the past two and a half years. Its largely unpoliced hinterlands, mostly empty desert and mountains, are used as bases for Islamic extremists.
* With additional reporting by Jahd Khail, Reuters and Agence France-Presse