* Streets calm after clashes this week
* President Conde widely expected to win second mandate
* Opposition leader denounces electoral fraud
* Delays reported, some voters not on list (Rewrites throughout after vote count starts, adds opposition quote, details)
By Saliou Samb
CONAKRY, Oct 11 (Reuters) - Millions of Guineans voted peacefully on Sunday in the West African country's second free election since the West African country's independence from France nearly 60 years ago.
Guinea - Africa's leading producer of bauxite, the raw material for aluminium - has a history of election violence linked to ethnic tensions, including in a 2010 vote that brought President Alpha Conde to power after military rule.
The 77-year-old Conde is widely expected to win a second mandate, although the results were expected to be close enough to require a second round, probably against main rival Cellou Dalein Diallo.
The streets were calm in the capital Conakry and elsewhere after clashes this week between security forces and supporters of rival parties that left several dead and dozens injured.
Plainclothes policemen stood vigil at schools and petrol stations transformed into voting booths where some waited for hours in the rain to cast their ballots.
Casting his vote in the Conakry neighbourhood of Boulbinet, Conde, dressed in a white tunic, reiterated an earlier call for calm. "I hope things go well because Guinea needs peace, Guinea needs unity," he told reporters.
At some polling stations, voting began only a few minutes behind schedule but in others there were complaints that paperwork and officials had not arrived by late morning.
Some voters' names were absent from the register.
"They told me to leave, they told me not to vote because they can't find my name or picture on the electoral list," lamented Abdulaye Barry, at voting station number eight.
The Independent National Electoral Commission (CENI) admitted on Saturday that about 7 percent of the electorate or hundreds of thousands of voters had not received cards, although it was not clear if this was deliberate or whether it had disadvantaged a particular party. It later extended voting by two hours to allow those affected by organisational delays to participate.
The president's opponents had sought a postponement of the vote, citing irregularities.
But in an attempt to defuse tensions between his mostly ethnic Peuhl supporters and those drawn from Conde's Malinke community, Diallo said on Saturday he would participate in the presidential election. Diallo also voted on Sunday and called for people to refrain from violence.
Sidya Toure, a former prime minister who placed third against Conde in 2010, denounced problems with the vote. "There was fraud everywhere...In these conditions, it is not a vote," he said.
Counting began late on Sunday and CENI is officially supposed to release results within 72 hours. An official said, however, that the provisional outcome was not expected before Oct. 15 or 16.
Analysts say that the most dangerous scenario would be a knock-out victory for Conde in one round, since polls have suggested the population of 11 million is deeply divided.
"Violence is still quite likely," Alexandre Breining, analyst with Africa Practice said by phone from Conakry. "There is a high chance that as soon as the provisional results are out, opposition leaders will ask supporters to take to the streets."
United Nations Secretary General Secretary-General Ban Ki-moon late on Saturday deplored the recent violence and called for political leaders to resolve disagreements through dialogue. A European Union observation mission was monitoring the vote.
Conde's campaign, whose slogan is "progress is on the march", has championed infrastructure projects to improve power supply in the poor, former French colony which for decades was run by dictators.
His opponents have sought to capitalise on his shortcomings such as the nearly two-year-old battle against the Ebola virus and declining investment in the mining sector.
But in a milestone for Guinea, no new Ebola cases were reported last week, although hundreds of people connected to the sick remain under surveillance. As a precaution, buckets of chlorine were placed outside polling stations. (Additional reporting by Luc Gnago in Conakry; Additional reporting and writing by Emma Farge in Dakar; Editing by Mark Heinrich and Grant McCool)
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