Amr Abdallah Dalsh / Reuters
Supporters of Egyptian President Mohamed Morsi and members of the Muslim Brotherhood chant pro-Morsi slogans during a rally in Cairo on Friday in the runup to Saturday's vote on a draft constitution.
Updated at 9:31 a.m. ET: Egyptians voted on Saturday on a constitution promoted by its Islamist backers as the way out of a prolonged political crisis and rejected by opponents as a recipe for further divisions in the Arab world's biggest nation.
Lines formed outside polling stations in Cairo and other cities and soldiers joined police to secure the referendum process after deadly protests during the build-up. Street brawls again erupted on Friday in Alexandria, Egypt's second city.
The opposition says the constitution is too Islamist and tramples on minority rights. Morsi's supporters say the charter is needed if progress is to be made toward democracy nearly two years after the fall of military strongman Hosni Mubarak.
Highlighting the tension in the run-up to the vote, nearly 120,000 army troops were deployed on Saturday to protect polling stations. Clashes between Morsi's supporters and opponents over the past three weeks have left at least 10 people dead and about 1,000 wounded.
"The times of silence are over," bank employee Essam el-Guindy said as he waited to cast his ballot in Cairo's upscale Zamalek district. "I am not OK with the constitution. Morsi should not have let the country split like this."
El-Guindy was one of about 20 men standing in line. A separate women's line had twice as many people. Elsewhere in the city, hundreds of voters waited outside polling stations for nearly two hours before stations opened at 8 a.m.
"I read parts of the constitution and saw no reason to vote against it," said Rania Wafik as she held her newborn baby while waiting in line. "We need to move on and I just see no reason to vote against the constitution."
In Alexandria on Friday, tensions boiled over into a street brawl between rival factions armed with clubs, knives and swords. Several cars were set on fire and a Muslim preacher who had urged people to vote "yes" to the constitution was trapped inside his mosque by angry opposition supporters.
NBC's Ayman Mohyeldin is outside the presidential palace in Cairo where hundreds of thousands are protesting what they say is an unjust constitution. They want to delay a vote on the current draft of the constitution now scheduled for December 15.
In the capital, Cairo, both sides made low-key final efforts to rally supporters.
Flag-waving Islamists gathered peacefully at one of the main mosques, some shouting "Islam, Islam'' and "We've come here to say 'yes' to the constitution."
Opposition supporters — who have been urged to vote "no" by their leaders — assembled outside the presidential palace.
The building remains ringed with police, soldiers and tanks after street clashes caused at least eight deaths earlier this month in violence prompted by Morsi's decision to award himself sweeping powers in order to ram through the new charter.
The referendum will be held on two days — this Saturday and next — because there are not enough judges willing to monitor all polling stations after some in the judiciary said they would boycott the vote.
Egyptians are being asked to accept or reject a constitution that must be in place before a parliamentary election can be held next year — an event many hope can steer the country toward stability.
The measure is generally expected to pass, given the well-organized Muslim Brotherhood's record of winning elections since the fall of Mubarak. Many Egyptians, tired of turmoil, may simply fall in line and vote "yes."
If the constitution is voted down, a new assembly will have to be formed to draft a revised version, a process that could take up to nine months.
Just over half of Egypt's electorate of 51 million will vote in the first round in Cairo and other cities. Polling stations opened at 8 a.m. (0600 GMT) and will close 12 hours later.
Official results will not be announced until after the second round, though it is likely that details will emerge after the first round that will give an idea of the overall trend.
The charter has been criticised by some overseas bodies.
The International Council of Jurists, a Geneva-based human rights group, said it falls short of international standards on the accountability of the armed forces, the independence of the judiciary, and recognition of human rights.
United Nations human rights experts said the draft should be reviewed to ensure that Egypt meets its obligations under international law on equality and women's rights.
To provide security for the vote, the army has deployed about 120,000 troops and 6,000 tanks and armoured vehicles to protect polling stations and other government buildings. While the military backed Mubarak and his predecessors, it has not intervened on either side in the present crisis.
Reuters and The Associated Press contributed to this report.
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