Nigeria votes in crucial presidential election

Polling stations opened in Nigeria Saturday with incumbent President Goodluck Jonathan favoured to win as Africa's most populous nation bids to hold its cleanest polls for head of state in nearly two decades.

Jonathan has staked his reputation on the conduct of the polls, repeatedly promising a free and fair election in the continent's largest oil producer long held back by corruption and with a history of vote fraud and violence.

His main challenger is ex-military ruler Muhammadu Buhari, who benefits from significant support in the country's north and has developed a reputation as an anti-graft figure, though his regime in the 1980s was also accused of outrageous rights abuses.

An enormous effort has been undertaken to hold a credible vote, but violence poses a serious risk, with bomb blasts and other attacks having killed dozens in the run-up to the polls, including during last week's parliamentary ballot.

A bomb exploded near a vote collating centre in northeastern Nigeria late Friday, but no casualties were reported, police said.

There were also reports of a second blast and shots being fired on Saturday morning in the city of Maiduguri, but details remained unclear, said Yushau Shuaib, a spokesman with the national emergency management agency.

"There was an attempted bomb attack on an (electoral commission) collation centre for Maiduguri metropolitan last night," state police commissioner Michael Zuokumor told AFP.

"The attackers, who were in a moving car, threw the bomb which exploded about 20 metres (yards) to the office, destroying shops and stalls around. However the office was unscathed," he said.

Zuokumor said no casualties were recorded. Maiduguri was hit by two explosions during parliamentary elections a week ago.

Tremendous hopes have been placed in the recently appointed head of the electoral commission, Attahiru Jega, a respected academic who ordered a series of reforms.

One of his main tasks was to do away with the previous voter list -- which was littered with false entries, including Mike Tyson and Nelson Mandela -- and compile a new one with electronic prints from each finger of every voter.

More than 73 million people have registered to vote in the vast West African nation.

But in an example of how difficult bringing about such change in Nigeria can be, a first attempt at holding parliamentary polls on April 2 had to be called off when material and personnel failed to arrive in a large number of areas.

When the parliamentary poll finally did go forward on April 9, officials and observers described them as a significant step forward for the country, though they were far from perfect.

Electoral officials are likely to be under more serious pressure on Saturday since turnout and tensions are expected to be higher.

Despite the violence, there was clear enthusiasm among voters across the country last week to cast ballots, and a number of them stayed behind in some areas to record the counting process on mobile phones.

Clips of vote counting were posted on YouTube, while updates were given on Facebook and Twitter. One local newspaper has run a daily graphic calling the voting period a "festival of democracy".

Scores of foreign and local observers have fanned out across the country, and several have pleaded with Nigeria not to let Africa down.

"There are other elections pending in many parts of our continent," former Ghana president John Kufuor, who is heading an African Union observer mission for the election, told AFP in an interview.

"If things should go awry here, I am afraid to think of what may transpire elsewhere. Nigeria is too important for Africa."

The ruling Peoples Democratic Party lost ground in last weekend's parliamentary vote, and opposition parties restarted negotiations this week in a bid to team up against Jonathan.

But those talks collapsed, leaving the opposition with a difficult path to unseat an incumbent running for a party that has won every presidential poll since Nigeria returned to civilian rule in 1999.

Jonathan, 53 and a southern Christian, is the first president from the main oil-producing Niger Delta region.

He has had an almost accidental rise to power that culminated with him being thrust into office last year following the death of his predecessor, Umaru Yar'Adua.

His calm approach has led some to call him weak, while others say it is better suited to bringing about change in Nigeria, a nation of some 250 ethnic groups and a population roughly split between Christians and Muslims.

Buhari, 69, is a northern Muslim who has run for president twice before. Many in the north see him as an opportunity to return power to their economically marginalised region.

There are two other main candidates in the race: Nuhu Ribadu, the former head of the country's anti-graft agency, and Ibrahim Shekarau, governor of the northern state of Kano.