Egyptian judges are investigating complaints of voting irregularities before declaring the official results of a referendum that is expected to confirm a controversial new constitution.
The probe could delay the announcement of results that was expected on December 24. The constitution was drawn up mostly by Islamists and was pushed to a quick referendum vote by President Muhammad Morsi.
Opponents of the constitution say it is too Islamic.
They have demanded a full investigation into alleged irregularities during the two stages of voting.
An unofficial tally issued by the Muslim Brotherhood says 64 percent of voters supported the draft constitution.
But turnout was light, with only a third of the 51 million eligible voters taking part.
An opposition tally was similar.
But the opposition says the ballot was skewed by abuses.
Based on reporting by Reuters, AP, dpa, and AFP