Congo Republic President Denis Sassou Nguesso has won a new five-year term with 60.39 per cent of the vote, the interior minister says.
The win extends his long rule over the oil-producing nation that first began in 1979.
Interior Minister Raymond Zephyrin Mboulou announced the result on state television and said opposition leader Guy-Brice Parfait Kolelas, who is popular in the south of the capital Brazzaville, won 15 per cent in Sunday's vote, while retired general Jean-Marie Mokoko won 14 per cent.
Opposition candidates have alleged election fraud and said on Wednesday that their own results show Sassou Nguesso headed for defeat.
The government has imposed a blackout on internet and mobile phone communications since Sunday, and it also banned the use of motor vehicles nationwide during the vote itself.
Sassou Nguesso came to power in 1979 and governed until 1992, when he lost an election. In 1997, he regained power after a civil war and then won elections in 2002 and 2009 at which there were allegations of fraud.
He campaigned this time on a promise to develop the country's infrastructure and commit a quarter of the state budget to education to tackle high youth unemployment in the nation of 4.5 million.
The 72-year-old pushed through changes to the constitution in a referendum last October to alter the term and age limits that would have barred him from standing for another five-year mandate.
