Egyptians will finally have a new president Sunday, 500 days after they ousted Hosni Mubarak at the beginning of their popular uprising in February, 2011.

Tensions were high as the secretary-general of Egypt's election commission, Hatem Bagato, said Saturday that commission head Faruk Sultan will announce the results at 3 p.m. local time Sunday.

Thousands of Egyptians held rallies in central Cairo late Saturday amid tight security to show support for both candidates — Muslim Brotherhood's Muhammad Morsi and former prime minister Ahmed Shafiq.

Muslim Brotherhood supporters continued to rally in Cairo's Tahrir Square, the heart of the 16-month uprising, chanting their support for Morsi, while Shafiq's supporters gathered near the memorial of the unknown soldier.

The official results were supposed to be released Thursday, but the election commission said it needed more time to investigate fraud allegations by both candidates.

But whoever wins, the new president will emerge with fewer powers than the candidates had expected when the army promised to hand over power to civilian rule by July 1.

Last week, the ruling Supreme Council of the Armed Forces carried out a series of moves aimed at solidifying its power, including the court-ordered dissolution of the Islamist-dominated parliament. The council also declared an interim constitution that gives its generals and the courts final say over much domestic and foreign policy, as well as the process to create a new, permanent constitution.

Muslim Brotherhood officials have warned of a confrontation between the people and the ruling military if Morsi is not named the winner. Supporters of both men have threatened a backlash should their candidate lose.