Three top contenders for Egypt's presidency were scrambling to stay in the race Sunday after the authorities disqualified them on technical grounds, prompting one to say that a major crisis threatened the nation's first free election.

The election is seen as the last step to democracy after more than a year of unstable army rule since Hosni Mubarak was overthrown by a street revolt. The generals are due to hand power to the new president by July 1, but the latest drama saw new accusations they were trying to prolong their influence.

Mubarak's former spy chief Omar Suleiman drew an outcry from opponents of the old regime when he entered the race last week, only to be told late Saturday that he had failed to secure enough signatures in one province to run, Reuters reported.

The two leading Islamist candidates were also disqualified, one because he has a criminal record - dating from what was widely seen as a political trial under Mubarak - and the other because his mother had taken U.S. citizenship, state media said.

All three have 48 hours to appeal to the state election committee against their exclusion. If their elimination is confirmed, it would redraw the electoral map just weeks before voting begins in May.

Lawyers for the candidates vowed to challenge the rulings, which can be reversed on appeal within 48 hours. Mohamed Hussein Tantawi, the field marshal who heads the military council that has served as Egypt's caretaker government since last year's revolution, agreed on Sunday to meet party leaders, the Financial Times reported.

A month ahead of Egypt's first presidential elections of any consequence or suspense, the country is beset by so many problems, on the brink of so many more, and faced with such uncertainty that it is perhaps no wonder many of its citizens are turning to God, while most of the rest are finding some comfort in the certainties of cynicism, said Elijah Zarwan, a fellow at the European Council on Foreign Relations.

We will not give up our right to enter the presidential race, said Murad Muhammed Ali, campaign manager for the Muslim Brotherhood's Khairat al-Shater, one of the three.

There is an attempt by the old Mubarak regime to hijack the last stage of this transitional period and reproduce the old system of governance.

The disqualifications add to the drama of a transition marked by spasms of violence and bitter political rivalries among Islamists, secular-minded reformists and remnants of the Mubarak order.

Shater, who became an immediate frontrunner after joining the race in late March, was disqualified due to past criminal convictions. Brotherhood members were often jailed for their political activities under Mubarak, who excluded the movement from formal politics.

Anticipating Shater's disqualification, the Brotherhood, which now dominates parliament following free elections held in the wake of Mubarak's removal, had nominated Mohamed Mursi, head of its political party, as a reserve candidate.

A lawyer for Salafi preacher Hazem Salah Abu Ismail, the most hardline of the various Islamists running for the post, said there would be a a major crisis now that his client was barred from the race.

On Friday, his supporters besieged the headquarters of the election commission, forcing it to evacuate the premises and suspend its work. Abu Ismail said the accusation that his mother held U.S. citizenship was fabricated by his political opponents.

The presidential committee has violated all the rules of law, Abu Ismail said in remarks published on his Facebook page. If the official decision is to violate the constitution, they should be able to deal with the consequences.

Military police and state security were guarding the headquarters of the election committee in Cairo on Sunday, state media reported.

Farouk Sultan, head of the presidential election commission, told Reuters a total of 10 of the 23 candidates had been disqualified.

Frontrunners still in the race include Amr Moussa, a former Arab League Secretary General and Egyptian foreign minister, and Abdul Moneim Abol Fotouh, who was expelled from the Brotherhood last year when he mounted his own presidential campaign.

In an interview with Reuters on Saturday, before his exclusion was announced, Suleiman said the domination of politics by the Brotherhood would hold the country back. But he said if he became president, the party could serve in his government and would be a vital part of Egyptian political life.

Suleiman, 74, said he was running for office in response to public demands for a counterweight to Islamist influence.

This is why they sought me, as a balance between Islamists and civilian forces, said Suleiman.

He describes himself as a devout Muslim but said that Egyptians fear their country is being turned into a theocracy.

The Brotherhood, in addition to dominating parliament, chairs an assembly that was formed to write a new constitution before a court suspended its activities last week. Liberal groups had walked out of the assembly, saying it failed to reflect Egypt's diversity.

Many people felt that the state is going to the Muslim Brotherhood - in parliament, in government and now the presidency, Suleiman said, while conceding that the Brotherhood was a very important segment of Egyptian society.

Some analysts saw a silver lining in the decision, which appeared to stick to the rules in a country increasingly characterized by lawlessness and backroom dealmaking. Voters were less outraged by the ruling than politicians.

The ruling shows that the law is above everyone, and that Egypt is a civilised country, and that no one can threaten or bend its arm, said Mohammad Ghitany, an Egyptian prosecutor.

What occurred reinforced the integrity and image of the election commission, said Said Sadek, a professor of political culture at American University in Cairo. It shows that it didn't take sides and that it was neutral and this puts them in a better light.

The exclusions appear to eliminate the most contentious political leaders, what some describe as a blessing in disguise. Both  Suleiman, viewed as the ousted Mubarak's right hand man, and Abu Ismail, whose religious pronouncements on everything from women's dress to the consumption of alcohol have outraged the country's liberals, are controversial figures. The Brotherhood, who has a less high-profile back-up candidate Mohamed Morsi, dominates parliament and trade associations and has enraged many Egyptians by reneging on a promise not to field a presidential candidate.