Gabon’s opposition leader has lodged a challenge to the presidential election result at the constitutional court.
Defeated presidential candidate Jean Ping has complained of fraud, pointing out that in one province incumbent Ali Bongo won 95% of the vote.
Former African Union chair Mr Ping lost the election by less than 6,000 votes.
The European Union has said there were "clear anomalies" in last month’s poll - charges denied by Mr Bongo, who in turn accused Mr Ping of fraud.
The official election result, announced on 31 August, gave Mr Bongo a second seven-year term with 49.8% of the vote to Mr Ping’s 48.2%.
Mr Ping criticised results in Mr Bongo’s home province of Haut-Ogooue, where turnout was 99.93% and 95% of votes were for the president.
Turnout in the other provinces was between 45% and 71%, according to Gabon’s interior ministry.
On Monday Gabonese Justice Minister Seraphim Moundounga resigned in protest.
The EU has also questioned the legitimacy of the election results.
But Mr Bongo retaliated, telling France’s RTL radio "some of the EU observers overstepped their mission".
When the election results were announced people took to the street in protest.
The Gabonese authorities say three people have died and 105 have been injured following violent clashes and more than 800 arrests.
Mr Ping puts the death toll higher - saying dozens of his supporters have been killed and that a presidential guard helicopter bombed his headquarters.
Gabon election: Bongo v Ping
Mr Bongo took office in 2009 after an election marred by violence
He succeeding his father Omar Bongo who had come to power in 1967 and was
Africa’s longest serving leader
Veteran diplomat Mr Ping had served as chair of the African Union
He had been a close ally of Omar Bongo and had been his foreign minister
He had two children with Omar Bongo’s daughter, Pascaline
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