Egypt's Hosni Mubarak was being kept alive by life support after the 84-year-old ousted leader suffered a stroke in prison Tuesday, officials said, deepening the country's uncertainty over who will succeed him. Both presidential candidates now claim to have won last weekend's runoff election.
The developments, which saw Mubarak moved out of prison to a military hospital, come 16 months after he was ousted by a popular uprising demanding democracy.
The Muslim Brotherhood, emboldened by its claims that its candidate won the election, sent tens of thousands of its supporters into the street. It was an escalation of its confrontation against the ruling generals over their grab this week of sweeping powers that give them dominance over the next president.
Some 50,000 protesters, mostly Islamists, protested in Cairo's Tahrir Square on Tuesday evening chanting slogans in support of the Brotherhood's candidate Mohammed Morsi and denouncing the generals.
"We, the people, gave them (the military) legitimacy and we now are taking back," said Saber Ibrahim, 36, a teacher who came from Beni Suef south of Cairo to participate in the rally.
The campaign of Mubarak's former prime minister, Ahmed Shafiq, said Tuesday he won the election, denying the Brotherhood's claim of Morsi's victory.
The election commission is to announce the official final results Thursday. No matter who it names as victor, his rival is likely to reject the result as a fraud.
The sudden health crisis of Mubarak, who is serving a life prison sentence, briefly overshadowed the politics. Details of his health crisis were sketchy.
Earlier, the state news agency MENA and officials said Mubarak suffered a "fast deterioration of his health." His heart stopped beating until he was revived by defibrillation, then he suffered a stroke. When Mubarak later arrived at the military hospital, he was "clinically dead," MENA reported. The news agency said doctors repeatedly defibrillated him with no initial response.
Later, a security official said Mubarak was on life support. The official spoke to the Associated Press on condition of anonymity because he was not authorized to talk to reporters.
Maj. Gen. Mohsen el-Fangari, a member of the ruling military council, told the Al-Shorouk newspaper website that Mubarak was in a "very critical condition," but denied he was dead.
Mubarak has been serving a life sentence since his conviction June 2 for failing to stop the killing of protesters during the 18-day uprising against his rule in February 2011.
Last weekend's president runoff was viewed as a landmark in Egypt's post-Mubarak transition -- the election of the first civilian president in 60 years.
Shafiq's campaign spokesman, Ahmed Sarhan, told a televised news conference Tuesday that Shafiq won 51.5% of the vote and that the claim of victory by Morsi was "false."
"Gen. Ahmed Shafiq is the next president of Egypt," Sarhan said. He said Shafiq won about 500,000 votes more than Morsi.
The Shafiq campaign's claim came just hours after Morsi's campaign repeated its claims of victory, saying Morsi had won 52% to Shafiq's 48%.
Shafiq, a former air force commander who was named prime minister during Mubarak's last days, is seen as likely to preserve the military-backed police state that his former boss headed for three decades. He, in turn, has presented himself as a strongman able to keep Egypt stable and out of the hands of the Brotherhood, playing on fears the group will turn the country into an Islamic state.
The military issued a constitutional declaration Sunday giving it legislative powers. A court ruling last week also dissolved the Islamist-dominated parliament.
