CAIRO (AP) -- A former strongman of ousted President Hosni Mubarak's regime announced his presidential candidacy Friday, shaking up an already heated race that is emerging as a contest between two longtime rivals -- former regime officials and Islamists who have surged in influence.
Omar Suleiman, one of the most powerful figures of Mubarak's regime, had said earlier this week that he would not run. But he said he changed his mind after hundreds of people rallied in Cairo to support a bid.
The announcement drew outrage from youth activists who spearheaded the popular uprising that toppled Mubarak last year and have since been disappointed by the continued influence of members of his ex-regime. Liberals and revolutionaries have been largely squeezed out of the presidential race. Some have vowed to boycott the May 23-24 balloting altogether.
"I find it incomprehensible that one of the top figures of the old regime, who should be on trial right now as a criminal, is actually considering running for president," said Mohammad Radwan, who took part in last year's mass protests.
The 75-year-old former general must get 30,000 signatures by Sunday's official filing deadline or the backing of at least 30 parliamentarians in order to run. Suleiman could be the ruling generals' preferred candidate, someone who would try to keep the old political system intact and protect the privileges of the military.
"This is a bullet to the Egyptian revolution," said spokesman Ahmed Khair of the liberal Free Egyptians Party. "His candidacy means that the revolution is not moving down its natural path and it means that the Egyptian citizen will the pay the price."
Suleiman, who appeared on television on Feb. 11, 2011 to announce that Mubarak would step down and hand power to the country's military leaders, served as Egypt's intelligence chief for 18 years at a time when the regime was accused of carrying out torture and human rights abuses against dissenters. He also was longtime a confidant of Mubarak.
That makes him suspect in the eyes of many Egyptians, who had hoped to stamp out the old regime altogether and usher in a transition to democracy.
A win for Suleiman would largely keep control of Egypt in the hands of the military. Egypt's last four presidents have all been military men.
His decision also was the latest surprise in the first presidential race since Mubarak was ousted after nearly 30 years in power.
Last week, the Muslim Brotherhood, Egypt's most organized Islamist movement, named its chief strategist and financier Khairat el-Shater as a candidate, reversing an earlier pledge not to participate in the election. The long-outlawed Brotherhood already controls about half of the seats in parliament and would completely dominate the political arena if el-Shater wins.
The Brotherhood's Freedom and Justice Party posted Suleiman's announcement to run for president on its official Facebook page, with five photos of him smiling and shaking hands with top Israeli officials to the backdrop of the Israeli flag.
"This is a serious threat to the revolution," a Brotherhood statement said Friday.
Suleiman, who was appointed vice president shortly after the uprising began, is well known and respected by U.S. officials and has traveled to Washington many times. He was the point person on both the U.S. relationship and the Israel-Egyptian relationship under Mubarak, once a close U.S. ally.
Suleiman's entry in the race is likely to be welcomed by Egyptians who fear their country might be slipping into chaos after a turbulent year of deadly protests against the military's continued rule that have battered the economy. His insider knowledge of the political system could make him one of the front-runners in the crowded field.
His supporters also fear that Egypt, the Arab world's most populous country, is falling into the hands of Islamists, some of whom have called for a strict application of Islamic law and cutting ties with neighboring Israel.
Hundreds rallied Friday in Cairo to call for him to run for president.
Suleiman said that helped change his mind.
"I can only meet the call and run in the presidential race, despite the constraints and difficulties I made clear in my former statement," he said in a statement carried by the official MENA news agency on Friday. He said he faces administrative obstacles, but did not elaborate.
Tarek Shalaby, a blogger and socialist activist, said he does not believe Suleiman has a strong chance of winning, though, since he was a central figure of Mubarak's widely despised regime.
Shalaby said Suleiman's bid will only push those fearful of Islamists to vote for presidential hopeful Amr Moussa, a former Arab League chief and foreign minister who is courting the liberal and secular vote. Shalaby also said he is boycotting the election because he does not believe it will be free or fair under military rule.
Meanwhile, thousands of ultraconservative supporters of Islamist candidate Hazem Abu Ismail, a 50-year-old lawyer-turned-preacher, rallied in Cairo's Tahrir Square to support him after it was announced that his mother was an American citizen, which could disqualify him as a candidate if he cannot prove otherwise. He has called it an "elaborate plot" against him and says his mother only had a Green Card. A preacher speaking to the crowd at Tahrir Square on Friday said the attacks against Abu Ismail amounted to attacks against God's rule.
The presidential vote is set to take place end of May, with a possible run off later. The announcement of who will lead Egypt is to be announced no later than end of June.