* Constitution backed by 57 percent in first round vote
* End of voting pushed back by four hours
* Rights groups report some irregularities
* Parliamentary election to follow if approved
CAIRO, Dec 22 (Reuters) - Egypt extended voting by four
hours on Saturday in the second and decisive round of a
referendum that was expected to approve the country's new
Islamist-drafted constitution after weeks of protests and
Islamist supporters of President Mohamed Mursi, who was
elected in June, say the charter is vital to move Egypt towards
democracy, nearly two years after an Arab Spring revolution
overthrew authoritarian ruler Hosni Mubarak.
It will help restore the stability needed to fix an economy
that is on the ropes, they say.
But the opposition says the document is divisive and has
accused Mursi of pushing through a text that favours his
Islamist allies while ignoring the rights of Christians, who
make up about 10 percent of the population, as well as women.
"I'm voting 'no' because Egypt can't be ruled by one
faction," said Karim Nahas, 35, a stockbroker, heading to a
polling station in Giza, a province included in this round of
voting which covers parts of greater Cairo.
At another polling station, some voters said they were more
interested in ending Egypt's long period of political
instability than in the Islamist aspects of the charter.
"We have to extend our hands to Mursi to help fix the
country," said Hisham Kamal, an accountant.
Queues formed at some polling stations around the country
and voting was extended by four hours to 11 p.m. (2100 GMT).
Unofficial tallies are likely to emerge within hours of the
close, but the referendum committee may not declare an official
result for the two rounds until Monday, after hearing appeals.
As polling opened on Saturday, a coalition of Egyptian
rights groups reported a number of alleged irregularities.
They said some polling stations had opened late, that
Islamists urging a "yes" vote had illegally campaigned at some
stations, and complained of irregularities in voter registration
irregularities, including the listing of one dead person.
The first round of voting last week resulted in a 57 percent
vote in favour of the constitution, according to unofficial
Analysts expect another "yes" on Saturday because the vote
covers rural and other areas seen as having more Islamist
sympathisers. Islamists may also be able to count on many
Egyptians who are simply exhausted by two years of upheaval.
Among the provisions of the new basic law are a limit of two
four-year presidential terms. It says the principles of sharia
law remain the main source of legislation but adds an article to
explain this further. It also says Islamic authorities will be
consulted on sharia - a source of concern to Christians and
If the constitution is passed, a parliamentary election will
be held in about two months. If not, an assembly will have to
be set up to draft a new one.
After the first round of voting, the opposition said a
litany of alleged abuses meant the first stage of the referendum
should be re-run.
But the committee overseeing the two-stage vote said its
investigations showed no major irregularities in voting on Dec.
15, which covered about half of Egypt's 51 million voters.
There was no indication on Saturday that the alleged abuses
were any worse than those claimed during the first round.
Even if the charter is approved, the opposition say it is a
recipe for trouble since it has not received broad consensus
backing from the population. They say the result may go in
Mursi's favour but it will not be the result of a fair vote.
"I see more unrest," said Ahmed Said, head of the liberal
Free Egyptians Party and a member of the National Salvation
Front, an opposition coalition formed after Mursi expanded his
powers on Nov. 22 and then pushed the constitution to a vote.
Protesters accused the president of acting like a pharaoh,
and he was forced to issue a second decree two weeks ago that
amended a provision putting all his decisions above legal
Said cited "serious violations" on the first day of voting,
and said anger against Mursi and his Islamist allies was
growing. "People are not going to accept the way they are
dealing with the situation."
At least eight people were killed in protests outside the
presidential palace in Cairo this month. Islamists and rivals
clashed on Friday in the second biggest city of Alexandria,
hurling stones at each other. Two buses were torched.
The head of the Muslim Brotherhood, an Islamist group that
represents Mursi's power base, said the vote was an opportunity
for Egypt to move on.
"After the constitution is settled by the people, the wheels
in all areas will turn, even if there are differences here and
there," the Brotherhood's supreme guide, Mohamed Badie, said as
he went to vote in Beni Suef, south of Cairo.
"After choosing a constitution, all Egyptians will be moving
in the same direction," he said.
The vote was staggered after many judges refused to
supervise the ballot, meaning there were not enough to hold the
referendum on a single day nationwide.
The first round was won by a slim enough margin to buttress
opposition arguments that the text was divisive. Opponents who
include liberals, leftists, Christians and more moderate-minded
Muslims accuse Islamists of using religion to sway voters.
Islamists, who have won successive ballots since Mubarak's
overthrow, albeit by narrowing margins, dismiss charges that
they are exploiting religion and say the document reflects the
will of a majority in the country where most people are Muslim.