Voting in Iran's presidential election has ended after an extension of four hours across the country and five hours in the capital Tehran because more people than expected appeared to have cast their vote.
|Al Jazeera's Soraya Lennie reports from Tehran just minutes before polls closed.
Friday's election, in which voters have a choice of six candidates, is the first for a head of government since a disputed 2009 ballot touched off months of political unrest in the Islamic Republic.
Polling stations were originally set to close at 6:00pm local time (13:30 GMT) on Friday, but voting was extended until 11:00pm local time (18:30 GMT).
Before polls closed, all six presidential contenders issued a joint appeal for calm.
"We ask people not to pay attention to rumours of victory parades being organised and to avoid gathering before the official results" are announced by the interior ministry, their statement said.
Earlier, Mostafa Moammad Najar, Iran's interior minister, told the Fars news agency that the voting hours had been extended because of a "rush of voters".
At the same time as choosing a new president from six candidates, voters will also pick municipal councillors.
Najar said early Saturday that preliminary election returns gave moderate Muslim leader candidate Hassan Rouhani a significant lead in the presidential race, according to AP news agency.
Najar said on state television that Rouhani has nearly 402,000 votes out of a total of 861,886 counted.
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If no presidential candidate secures 50.1 percent or more of the votes to win outright, a second round will be held a week later.
Several witnesses, who visited polling stations in Tehran earlier on Friday, said that there were more people waiting to vote than at the previous election in 2009, according to Reuters.
Iran's supreme leader Ayatollah Ali Khamenei, who called for a large turnout but did make his preference public for any single candidate, cast his ballot in the capital Tehran at the Hosseini Imam Khomeini Mosque in the Beit Rahbari compound early on Friday.
"Among those running ... I had someone in mind who I chose. I haven't told anyone [of my vote]," he told state television as he voted.
"Even those close to me like my family and children don't know who I voted for."
Khamenei derided Western misgivings about the credibility of the vote.
"I recently heard that someone at the US National Security Council said 'We do not accept this election in Iran'," he said. "We don't give a damn."
Rouhani has also cast his ballot in Tehran.
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"I have come to destroy extremism and when I see that these extremists are worried by my response and my vote I am very happy. It means that with the help of the people we can instill the appropriate Islamist behaviour in the country," he said after voting.
With the conservative camp divided, reformists seem confident of a good showing by Rouhani, the former chief nuclear negotiator, who has emerged as a frontrunner. According to analysts, there is a possibility of a run-off.
|Presidential candidate Hassan Rouhani casts his ballot in Tehran.
Al Jazeera's Soraya Lennie, reporting from Iran, said that Rouhani was earlier not thought of as a serious contender, but since the endorsements of two former presidents, pro-reform Mohammad Khatami and pragmatist Akbar Hashemi Rafsanjani, there had been increasing excitement in Tehran over his candidacy during the past 24 hours.
A group of three heads the conservative camp: former foreign minister Ali Akbar Velayati, Tehran Mayor Mohammad Baqer Qalibaf and the republic's chief nuclear negotiator, Saeed Jalili.
Both sides, reformist and conservative, have appealed for the electorate to turn out in high numbers - the first hoping for change, and the other to show the power of a regime accused of seeking to ensure victory for a Khamenei loyalist.
For both camps, the important issue will be to mobilise abstentionists who demonstrated against Ahmadinejad's re-election in 2009, alleging massive electoral fraud.
Source: Al Jazeera and agencies