More than 90% of voters have backed Egypt's new constitution, election officials said.
State media reported that 37% of registered voters cast a ballot in the referendum on the draft charter that is to replace the one introduced under the rule of ousted president Mohammed Morsi.
Ballots are still being counted and final results are expected before the end of the week.
The vote, held over two days, was boycotted by members of Morsi's Muslim Brotherhood and criticised by international monitoring groups.
"Those who voted 'yes' were saying yes to building and saying no to all those who want destruction," said interim prime minister, Hazem el-Beblawi.
During the first day of voting nine people were killed in clashes between Morsi supporters and security forces.
A man was shot dead on the second day, as students rallying outside the campus of the University of Cairo clashed with police. More than 20 people were arrested, authorities said.
The government installed after Morsi was toppled in a military coup campaigned intensely ahead of the vote with the backing of pro-military media, which portrayed the referendum as key to the nation's security and stability.
Monitoring group Transparency International said that the campaign before the vote was affected by "severe limits on the freedom of expression, association, and assembly".
"The political context in the run-up to the referendum impaired conditions to hold a free and fair referendum compared with international standards," said Kol Preap, the head of a Transparency International mission.
Preap said that government actions such as arresting critics "undermined a level playing field for the promotion of diverse views".
The constitution draft limits Islamic law and bans political activity based on religion.
It also boosts the army's powers by giving it the priority to name the defence minister over the next two presidential terms and protects equal rights between men and women.