Presidential candidate of the All Progressives Congress (APC) and former army general Muhammadu Buhari speaks during a press conference in Kano, northern Nigeria, on January 21, 2015. Nigeria's main opposition candidate today rejected claims about hi ~ AMINU ABUBAKAR
Abuja - A court ruling on Wednesday effectively blocked an attempt to bar the main opposition candidate from running in what looks set to be the closest presidential race since military rule ended in 1999.
The court adjourned the case until April 22, leaving Muhammadu Buhari free to stand against President Goodluck Jonathan in the March 28 election.
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Jonathan's supporters had sought to disqualify the former military ruler on the grounds that he had forged his secondary school certificate, a charge the ruling People's Democratic Party (PDP) has widely publicised and which is seen more as a smear campaign than a serious accusation.
"They are interlopers and busy bodies who want to waste the time of this court," Justice Adeniyi Ademola said of the plaintiffs who brought the petition.
Both the PDP and Buhari's All Progressives Congress (APC) have mounted so far unsuccessful challenges to the eligibility of each other's candidates to rule Africa's biggest economy and top oil producer.
Investors, electoral observers and foreign powers will be closely watching how the country conducts the presidential and parliamentary polls. Past polls have been marred by ballot box stuffing, thuggery and in some cases completely fictitious results, although the one that gave Jonathan his first elected term in 2011 was deemed the fairest yet.
In a separate case this week, the Nigerian federal high court in Lagos barred the military from deploying near polling stations during the election, after the opposition raised fears that soldiers could be used to rig the vote.
The multiple court cases underline the ethnic, regional and in some cases religious divisions among the electorate: Jonathan is a southern Christian from the oil-producing Niger Delta while Buhari is a Muslim from the semi-arid north.
Neither side is likely to concede defeat, raising fears that violence could follow. When Buhari lost to Jonathan in 2011, 800 people died in three days of riots that left 65,000 homeless.
The foreign ministry said on Wednesday that Nigeria would close its land and sea borders from midnight on March 25 until midnight on March 28 to ensure security.
World powers fear even more protracted bloodshed this time.
"I call on all leaders and candidates to make it clear to their supporters that violence has no place in democratic elections," U.S. President Barack Obama said in a message to Nigerians on Monday.
"It is the responsibility of all citizens to help keep the peace, no matter who wins."
Army Chief of staff Lieutenant-General Tobiah Minimah said on Wednesday the security forces had "made adequate arrangements for security during the elections."
The Nigerian military said it detained two al Jazeera journalists on Wednesday in their hotel in the northeastern city of Maiduguri, in an area plagued by an Islamist insurgency, and seized their equipment, saying their presence was unauthorised.
"Foreign journalists have been cautioned against unauthorised movements around military operations," it said.