Samura Kamara, the losing candidate in last month's presidential elections in Sierra Leone, has appealed to the Supreme Court to overturn the result, just days after he congratulated the declared victor, Julius Maada Bio, according to documents seen by AFP on Thursday.
In a petition to the West African state's top court, Kamara said the electoral process was "fundamentally flawed" and the declaration in favour of Bio "was invalid and cannot be supported in law."
The spokesperson for the National Electoral Commission (NEC), Albert Massaquoi, said the petition was filed on Wednesday evening.
"We have informed our legal team and they will take it from there. It is all part of the democratic process," said Massaquoi.
The petition says the NEC acted illegally when on April 4 it issued the final results of the second and final round of the elections, which took place on March 31.
The commission included results of polling stations where there had been "over voting," it alleges. Results from polling stations where "over voting" occurred should thus be stripped out, it says.
The date for a decision by the Supreme Court was not immediately known.
Bio, a former soldier who briefly led a military junta more than two decades ago, was credited with 51.81% of vote in the runoff.
Kamara - champion of the All People's Congress (APC), which had been in power for a decade - secured 48.19%.
Kamara, on the evening of the election results, had said he would contest the outcome.
But last Saturday he went to Bio's residence, congratulated him and vowed to throw the APC's support behind the new administration.
His show of support was widely welcomed as a way to ease post-election tensions.
Bio will need the support of the APC, which has 68 out of 132 parliament seats, to form a workable government majority in what is one of the world's poorest nations despite huge mineral and diamond deposits.
Its economy is still recovering from war and disease and remains fragile with investors slowly returning, while corruption is widespread.
Sierra Leone's neighbours and international observers say the vote was generally conducted peacefully, and Bio has received congratulatory messages from around the world.
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