Voting in Mauritania's presidential election passed off peacefully under a scorching sun on Friday, but well before the polls closed, opposition candidates were accusing President Maaouiya Ould Sid'Ahmed Taya of trying to rig the result in his favour.
By noon, Mohamed Khouna Ould Haidalla, a former military head of state who was overthrown by Ould Taya 19 years ago, and Ahmed Ould Daddah, a half-brother of the first president of this desert state of 2.5 million people, were both crying foul.
"As we predicted earlier, fraud is in fact very definitely taking place," Ould Daddah told IRIN as his campaign supporters handed out a list of alleged voting irregularities. This cited instances of opposition representatives being barred from polling stations, people being allowed to vote without presenting proper identification, double voting, voting by proxy and vote buying by supporters of Ould Taya.
A spokesman for Ould Haidalla meanwhile complained that fraud was widespread in the interior of this former French colony, where polling was less exposed to independent scrutiny.
The opposition claims that Ould Taya rigged both the previous presidential elections in 1992 and 1997 to allow him to retain his iron grip on power in this poor staunchly Islamic country that is riven by complex ethnic divisions and clan rivalries.
But Ould Taya's campaign director, Hamoud Ould M'hamed, dismissed the opposition's haste to denounce fraud as "deplorable."
"It is simply lamentable to cry fraud for the past year, to cry fraud well before the campaign started and that, on the day of the election, only two hours after voting started, to cry fraud and ballot stuffing," he told reporters.
Ould Taya has moved over the years from being a staunch friend of former Iraqi leader Sadaam Hussein to a close ally of the United States and France. Unusually for a state with Islam written into its constitution, he even established full diplomatic relations with Israel - a move that proved controversial at home.
Five opposition candidates challenged Ould Taya's bid for a fresh six-year term. But Ould Haidalla, who has attracted broad support from liberal reformers, Islamic militants and former Ould Taya supporters, appears to have worried the incumbent head of state most.
Last Tuesday, two of Ould Haidalla's sons were arrested, on Wednesday the former army colonel was accused by the government of plotting a coup, and on Thursday afternoon, hours before polling stations were due to open, Ould Haidalla himself was arrested and held for several hours before being released.
Voting procedures were more transparent this time than in previous elections. New voter cards that are more difficult to forge, were introduced, the complete voters' roll of over 1.1 million names was published on the internet and transparent ballot boxed were introduced that are more difficult to stuff discreetly with phantom ballots.
But the government banned both local and foreign observer teams from formally monitoring the election and there were widespread fears that after voting stopped at 1900 GMT, the ballot boxes would be tampered with before counting began.
"It is not the voting that is the problem, but the counting," one man told IRIN in Nouakchott as he left a polling station.
Human rights lawyer Brahim Ould Ebety, who formed part of an unofficial independent observer team that was not recognised by the government, told IRIN that during the 12 hours of orderly polling in the capital he had observed "irregularities" in voting procedures than obvious fraud.
Official results from the election were expected to start trickling in overnight, but campaign officials said a clear national trend would probably only emerge on Saturday or Sunday. If no candidate wins more than 50 percent of the vote, the two front-runners will face each other in a second round election on 21 November.