Thousands of supporters of Mali's defeated opposition election candidate took to the streets in Bamako Saturday to protest the poll result, organisers said.
The demonstrators waved banners with the slogans "No to the declared results" and "IBK (Ibrahim Boubacar Keita) will not steal our victory".
Opposition candidate and former minister Soumaila Cisse, 68, has slammed the August 12 vote that handed a second term to his opponent Keita as marred by fraud.
Cisse polled 32.84% of the vote according to the official count, compared to 67.16% for incumbent Keita.
"We want a country that is peaceful, tranquil, stable but not a country in which the president is elected by fraud, ballot stuffing and the falsification of results," Cisse said during the march in Bamako, which was initially banned but later given authorisation by the authorities.
The demonstration, which was flanked by police and held without incident, started with some 5 000 people and swelled to "about 50,000", according to Cisse spokesperson Djiguiba Keita.
A Malian police source, however, said the protest had garnered "a few thousand people".
In the central city of Nioro several hundred people also took to the streets in protest, according to organisers.
"Nioro will stay mobilised for this democratic fight. We are not going to give up because if this situation continues like this no-one will ever win an election against IBK and his clan" said Abdoulaye Diallo, a Cisse supporter and march organiser in Nioro.
Keita, 73, who will begin his second five-year term on September 4, has called on Cisse to accept the result.
Cisse aides said more were being held in other parts of Mali and also abroad.
Hundreds of Cisse's supporters have gathered in recent days to protest the result.
But the Constitutional Court rejected a petition from Cisse against the result as being inadmissible or unsupported by evidence.
"This institution has discredited itself as a voluntary prisoner of an autocratic regime," Cisse said Thursday, referring to the court.
Observer missions sent by the European Union and the African Union (AU) have said the election was not badly impaired.
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