Nigerians go to the polls in key for president,

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Nigeria election, 2015 by mohsin-naqvi

Nigerians go to the polls in key presidential election
28 March 2015 Last updated at 22:49 GMT
Africa's most populous nation, Nigeria, has been voting in presidential elections.
The current President Goodluck Jonathan is standing for a second term.
But he is facing a strong challenge from Muhammadu Buhari, a former military ruler.
Security is a key issue and there has been some sporadic violence at a number of polling stations.
Andrew Harding reports.