A majority of the Egyptians who cast their ballots in a referendum have backed a disputed draft constitution favoured by President Mohammed Morsi and his Islamist allies, unofficial results showed Sunday, DPA reported.
Voters turned out in big numbers in Cairo and in most of the 10 provinces where the first round of voting occurred Saturday.
The state-run Al Akhbar newspaper reported that 59 per cent of the votes counted were in favour of the Islamist-backed constitution. The Muslim Brotherhood's Freedom and Justice Party calculated support at 57 per cent.
State television's website meanwhile reported that 68 per cent of Cairo voters had rejected the charter, highlighting a long-standing split in attitudes between the heavily populated capital city and Egypt's more conservative rural regions.
The mostly liberal opposition and independent monitors alleged the polling had been marred by massive irregularities.
Eight local rights groups on Sunday called for the first round of voting to be held again, citing widespread violations.
Bahey al-Din Hassan, the head of the Cairo Institute for Human Rights Studies, one of the eight groups, said alleged violations included preventing civil society monitors from attending the counting process, while allowing access for representatives of the Muslim Brotherhood.
Hassan also cited alleged illegal canvassing by Islamists, the disruption of voting in some centres, lack of full judicial supervision and the closure of some polling stations ahead of schedule.
The second phase of the polling is due in the rest of the country on December 22.
The Muslim Brotherhood, from which Morsi hails, Sunday called on voters in the districts where the second round will be held to show up in larger numbers than those of the first phase.
"We hope this referendum will end acts of chaos, sabotage and thuggery," added the organization in a statement.
Angry protesters have in recent weeks attacked and torched Brotherhood offices in several areas of Egypt.
For his part, opposition leader Mohammed ElBaradei, who campaigned for a "No" vote, said divisions were growing in the country.
"However, the level of consciousness is growing rapidly and Egypt of the revolution is within reach," he wrote on Twitter, referring to the significant percentage of voters who opposed the constitution.
The opposition says the constitution, drafted by an Islamist-led constituent assembly, could undermine women's and political rights, and sideline minorities.
Critics also say the charter is heavily influenced by Islamists.
Southern provinces saw high percentages in favour of the constitution, including 83 per cent in Aswan and 77 per cent in Sohag, according to non-official results of the Saturday vote.
Voters in Morsi's Nile Delta hometown Sharqia supported the disputed constitution with 65.6 per cent of the valid ballots cast in their province on Saturday, said local media.
Islamists have heavily campaigned in favour of approving the draft constitution, arguing that it is necessary to fast-track the transition from Hosny Mubarak's authoritarian rule.
The official result is to be announced after the second and final round of voting takes place in the country's remaining 17 provinces.
If the constitution is approved, Morsi will call an election for a new lower house of parliament. The Shura Council, or upper house, will be given the authority to legislate until a new legislature is elected.
If the draft constitution is voted down, Morsi will call an election within three months to pick an assembly to write a new constitution.