The legitimacy of the Nigerian presidential election is under threat after two of its main frontrunners criticised the way the poll had been carried out.
Yesterday's poll was the first attempt to democratically hand over power from one civilian president to another since the west African country won independence from Britain in 1960.
Although historic the occasion was marked by reports of violence up and down the country, with reports of ballot boxes stolen, police both opening and receiving fire and the abduction of election officials.
One bomber even attempted to blow up the country's electoral commission headquarters with a lorry laden with fuel and gas cylinders, but his attack was unsuccessful.
The election also saw polling stations forced to remain open beyond the scheduled voting period because of delays in the delivery of vital voting materials – including ballot papers.
"It is not a question of winning because I don't think there have been elections," the Reuters news agency quoted Muhammadu Buhari as saying.
Meanwhile the AFP news agency quoted Atiku Abubakar, Nigeria's current vice president, as describing the vote's "intimidation, fraud and low participation".
Up to 65 million people were eligible to vote in the country's 120,000 polling stations.
Results are expected tomorrow. If no clear winner emerges a run-off vote will take place.
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