An overwhelming majority of Egyptians who voted on the country's new constitution have backed the draft charter, a senior Egyptian official said today.
An international monitoring group criticised the clampdown ahead of the vote and said authorities had imposed "severe limits" on freedom of expression.
The election official said unofficial results, after most of ballots have been counted, indicate that more than 90% of the voters have said "yes" to the constitution. He declined to give an estimate on the final turnout.
Meanwhile, Nabil Salib, the head of the Supreme Election Committee, was quoted by the official MENA news agency as saying ballots were still being counted and that final results would be announced in a few days. He initially said the results were expected tomorrow and in general, results are usually announced within 72 hours after polls close in Egypt.
The vote held on Tuesday and yesterday is a milestone for Egypt's interim government, installed by the military after the ousting last July of Islamist President Mohammed Morsi, following mass protests demanding that he step down.
The draft is also a key piece of a political roadmap toward new elections for a president and a test of public opinion about the coup that removed Mr Morsi. It is a heavily amended version of a constitution written by his Islamist allies and ratified in December 2012 with some 64% of the vote but with a nationwide turnout of just over 30%.
Mr Morsi's Muslim Brotherhood group and other Islamist groups boycotted the referendum, calling it "illegitimate." The country's second-largest Islamist group, the ultraconservative Salafis, have largely stayed away from the polls, apparently in response to a crackdown against Islamists that included confiscation of their assets, shutdown of their TV networks and the banning of their top clerics from preaching in mosques.
This left traditional Islamist strongholds across Egypt seeing only a trickle of voters during the two-day balloting.
By contrast and raising the prospects of a continued polarisation among Egyptians, long lines formed outside polling stations in major urban areas and big cities, with crowds brandishing posters of the country's military chief, chanting in support of the army and women ululating.
Such patriotic outbursts followed an intense campaign by the government and the overwhelmingly pro-military media, which portrayed the balloting as key to the nation's security and stability.
In the weeks before the vote, hundreds of thousands of fliers, posters, banners and billboards urged Egyptians to vote "yes" in the referendum. People were arrested for posters and campaigns calling for a "no" vote.
The current interim government is looking for a big "yes" majority and large turnout to win undisputed legitimacy and perhaps a popular mandate for the military chief, Gen. Abdel-Fattah el-Sissi, to run for president later this year. But silencing dissent has raised questions about the legitimacy of the process.
Gen El-Sissi has yet to say outright whether he plans to seek the nation's highest office, but his candidacy appears increasingly likely every day.
Kol Preap, the head of a Transparency International mission that monitored the referendum, said in a report today that while authorities had responded to "a deep desire by the majority of Egyptians to move toward a democratic path," the political environment around the vote created "severe obstacles to advancing democracy."
Mr Preap cited "severe limits on the freedom of expression, association, and assembly" in the campaign ahead of the vote. His group had eight observers in 15 out Egypt's 27 provinces.
"The political context in the run-up to the referendum impaired conditions to hold a free and fair referendum compared with international standards," he added. Government actions such as arresting critics "undermined a level playing field for the promotion of diverse views."
Amr Moussa, the head of the panel that drafted the charter told the pan-Arab daily Asharq Al-Awsat he believes el-Sissi is making up his mind to run in the race.
"I believe that Gen el-Sissi is likely to run" for president, he told the paper in a Thursday interview. "We need a nationalist figure trusted by the people, one who we are sure will not take the country into an abyss."
Following the referendum, Egypt's Interim President Adly Mansour is expected to also announce a change in the army's roadmap and schedule presidential elections before the vote for the next parliament. This could give Egypt a new president before the summer.