Gabon opposition leader Jean Ping has lodged a challenge with the country's Constitutional Court, contesting the result of a presidential vote whose validity has been questioned at home and abroad.

Election results announced last week showed incumbent Ali Bongo beating Ping by a slender margin of fewer than 6,000 votes, sparking days of deadly riots in the capital, Libreville.

Jean Gaspard Ntoutoume Ayi, president of Ping's communication team, said on Thursday that the opposition leader had asked the court to authorise a recount of the votes in a southeastern province, where Bongo won 95.5 percent of the vote.

"Ping's demand is for a recount of the votes in the province of Haut-Ogooue, voting bureau by voting bureau," Ayi told reporters

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Results from the province, which is a heartland of Bongo, showed a turnout of more than 99 percent, compared with a nationwide turnout of 59.46 percent.

Having previously expressed doubts about the court's independence, Ping was "very reluctant" to lodge the complaint, Al Jazeera's Catherine Soi, reporting from Libreville, said.

"But he says he has to follow the law," our correspondent added. "The government [also told him], 'if you have a complaint you need to go to court. Without that we cannot move forward'.

"Now the judges have 15 days to either throw out the case or invalidate the results."

'Clear anomaly'

Ping's challenge came days after EU election observers raised questions over the result in Haut-Ogooue in the August 27 poll.

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"An analysis of the number of non-voters as well as blank and disqualified votes reveals a clear anomaly in the final results in Haut-Ogooue," Mariya Gabriel, the head of the EU observation mission in Gabon, said in a statement on Tuesday.

"The integrity of the provisional results in this province is consequently compromised."

Bongo, whose family has ruled Gabon for nealy half a century, hit back at the EU criticism on Wednesday, accusing the observation mission of bias.

"I would also have liked them to have noted some anomalies in the fiefdom of Mr Ping. If we are raising anomalies, we have to be clear, balanced and raise all the anomalies that have been noted," Bongo told France's RTL radio, in an interview broadcast on Wednesday. 

Post-election clashes

Ping has previously described the election as fraudulent and has demanded a recount - a call echoed by Manuel Valls, prime minister of Gabon's former colonial power, France.

Bongo has also accused Ping of "committing fraud" and said that only the Constitutional Court could order a recount.

Post-election clashes between Ping's supporters and security forces resulted in the deaths of between 50 and 100 people, Ping said on Tuesday. The government's official casualty count stands at three dead.

The parliament in the capital, Libreville, was also torched in protests over the result.

Source: Al Jazeera News And Agencies