Egyptians began voting on Monday in a presidential election expected to sweep former army chief Abdel Fatah al-Sisi into office, reviving rule by strongman three years after Hosni Mubarak's downfall.

Voters cast ballots at heavily guarded polling stations from 9.00 a.m. local time. Sisi, who deposed the Muslim Brotherhood's Mohamed Morsi last July, faces only one challenger in the two-day vote: the leftist politician Hamdeen Sabahi.

"We see Sisi as a real man. Egypt likes a strong man," said Saber Habib, clenching his fist to ram home his point as he waited to vote in the city of Suez, east of Cairo.

"We want the country to move forward and for the people to have bread," said the 64-year-old contractor.

'We see Sisi as a real man. Egypt likes a strong man.'- Saber Habib, 64-year-old contractor

Widely regarded as Egypt's de facto leader since he toppled Morsi following mass protests, Sisi faces manifold challenges including an economy in crisis and an Islamist insurrection that has spiralled since Morsi's downfall.

As voting began, a homemade bomb exploded outside a polling station in the city of El-Mahalla El-Kubra, north of Cairo, state TV reported. No casualties were reported.

Although the result appears a foregone conclusion, a big turnout would be seen as a strong mandate for Sisi.

"We need someone who will from day one put the country on the right track," said Ahmed El-Demerdesh, a mechanical engineer, as he waited to vote in Cairo. "We can't take any more experiments."

Egypt election

Presidential hopeful Hamdeen Sabahi is trying to rally youth behind him as the hope for the country's pro-democracy "revolution" in his race against the former military chief Abdel-Fattah el-Siss. (Amr Nabil/The Associated Press)

As he voted in Cairo, Sisi waved to supporters, who shouted "President, President!"

Supporters regard Sisi, who resigned from the military earlier this year, as a decisive figure who can stabilize Egypt, a strategic U.S. ally in the heart of the Arab world.

His opponents, mostly in the Islamist opposition, say he is the mastermind of a coup that robbed Egypt's first freely elected leader of power.

They fear Sisi will rule Egypt with an iron fist just like other former military men did, and that he will protect the political and economic interests of the generals and businessmen who amassed fortunes before the 2011 uprising which toppled Mubarak but remain influential.

The Brotherhood has called for a boycott of the vote it has described as a farce. "What happened in Egypt was wrong and the best message against it is to boycott this vote," said Abdel Karim Mohamed, a 45-year old accountant, speaking in hushed tones as he parked his motorbike near a polling station.

Security forces have largely driven the Brotherhood underground after hundreds were killed and thousands arrested. More than a thousand Brotherhood supporters have been sentenced to death on charges including inciting violence after the army overthrew Morsi.

Since the army overthrew the king in 1952, Egypt has been ruled by a series of military men including Gamal Abdel Nasser and Anwar Sadat, a pattern briefly interrupted by Morsi's one year in office.

Human rights concerns

Foreign governments condemned the rulings against the Brotherhood but none has taken concrete steps to pressure Egypt into improving its human rights record.

"Egypt's presidential elections will not wipe the country's human rights record clean after 10 months of gross violations," rights group Amnesty International said.

Members of the pro-democracy movement that led the protests against Mubarak in 2011 have also been jailed, and many cases of torture by the security services have been reported by human rights groups.

Sisi must tread cautiously. Abuse by police was one of the triggers for the 2011 revolt. Although supporters hailed Sisi as a hero when he removed the Brotherhood from power, there is growing discontent over rights abuses in the streets.

Secular activists have become more vocal since the security crackdown against Islamists was expanded to include liberal groups, including the April 6 movement which helped to start the 2011 uprising but has since been banned.

On Saturday, hundreds of people marched through downtown Cairo calling for an end to what they called military rule.

"Down with the military regime! The voice of the revolution is coming from the streets and the factories!" the crowd of mostly young men and women shouted.

"Bread! Freedom! Social justice!" they chanted, echoing more of the rallying cries of the 2011 uprising.

Mahmoud Omran, a 23-year-old student who spent four months in Cairo's Tora Prison after participating in street clashes in 2011, called the election "pointless".

"Why vote? No matter what percentage Sisi wins by, he will be president after spilled blood," he said.

'Why vote? No matter what percentage Sisi wins by, he will be president after spilled blood.'- Mahmoud Omran, 23-year-old student

Though Sisi's support appears to be shrinking, many Egyptians worn down by three years of political turmoil still view him as a hero for ending Morsi's divisive time in office.

"Sisi saved us from the Brotherhood and what they were doing to us," said Ibrahim, 47, who works for an import-export company in Cairo.

Monitors from the European Union and U.S.-funded Democracy International are observing the vote, and more than 400,000 members of the security forces have been deployed to secure polling stations across the country.

Sisi secured 95 per cent of votes cast in advance by Egyptians overseas, but an opinion poll by the Washington-based Pew Research Centre suggests a more mixed picture inside Egypt, with Sisi viewed favourably by 54 per cent and unfavourably by 45 per cent.

The Muslim Brotherhood and its Islamist allies have vowed to escalate a "revolutionary wave" this week, though it has been many months since they were able to mobilize large numbers in the streets. The Brotherhood has urged its supporters to boycott the election.