Egyptian demonstrators incensed that ousted leader Hosni Mubarak's last prime minister has advanced into a run-off presidential election have vandalized his main campaign office and set it on fire after officials confirmed the vote results.
Emergency personnel said late Monday the blaze at Ahmed Shafiq's Cairo headquarters had been extinguished and that no one was hurt.
Earlier, several thousand protesters gathered in Cairo's Tahrir Square and other venues across Egypt, chanting slogans against the military, Shafiq and the Islamist Muslim Brotherhood's candidate, Mohammed Morsi.
The count from Egypt's first free presidential race last week showed the Brotherhood's Morsi as the top vote-getter and secularist Ahmed Shafiq a strong second.
Shafiq is widely viewed as an extension and symbol of Mubarak's rule and his run-off against Morsi is the most polarizing result possible. The outcome has divided Egypt and deeply disappointed the activist movement that galvanized the nation's 2011 revolt against Mubarak's entrenched old guard.
The presidential vote results were being contested even before they were released.
The expected three top candidates filed appeals with the election commission, alleging violations and fraud. Socialist Hamdeen Sabahi called for a partial vote recount in five provinces where the results are in dispute.
The presidential runoff, to be held June 16-17, will offer Egyptians a stark choice between candidates from divergent paths.
Morsi netted 5,764,952 votes, slightly ahead of Shafiq with 5,505,327. Sabahi took third place with more than 4.8 million votes, ahead of moderate Islamist Abdel Moneim Abul Fotouh with a little over 4 million. Former foreign minister Amr Moussa placed fifth, trailing with 2.58 million votes.
The commission said turnout was 46 percent of the 50 million Egyptians who were eligible to vote.
Morsi was not his Islamist group's first choice for its presidential candidate. But he got the role when the Brotherhood's lead candidate was disqualified, and then became a front-runner in a show of the group's political muscle.
During the campaign, Morsi delivered fiery speeches and vowed his presidency would be based on Islam but not be a theocracy.
Shafiq was Hosni Mubarak's last prime minister before he lost power during last year's pro-democracy protests.
The former Air Force commander was appointed prime minister in hopes of appeasing the popular revolt. But because of that connection to Mr. Mubarak, he is viewed with some suspicion by activists involved in the 2011 movement and has polarized voters.
A presidential victory for one of the secularist candidates would mark a significant turn from parliamentary elections just six months ago when more than 70 percent of Egyptian voters cast ballots for Islamist parties.