Abuja, 28 Mar - (ANA) - Elections in parts of Nigeria have been extended until Sunday after delays and a number of attacks.

The delays were "not widespread" but were still "a matter of concern", an election official said.

Technical problems with new biometric cards slowed down voter registration, even affecting President Goodluck Jonathan. President Jonathan tried for 50 minutes to register in his home village of Otuoke, before coming back a second time. When the electronic registration failed again, he had to be accredited manually and did eventually cast his ballot paper. Problems were also reported from the north's biggest city of Kano, where thousands of voters waited for election officials and voting materials to arrive. Gen Buhari did not have any problems registering in his hometown Daura. More than 20 people have reportedly been killed in various attacks by unknown gunmen. Mr Jonathan is facing a strong challenge from former military ruler, Muhammadu Buhari. The election is said to be the most closely fought since independence. It was postponed from mid-February to allow the army time to recapture territory from the Islamist militants of Boko Haram. The two main candidates had pledged to prevent violence during and in the aftermath of the elections. But several hours after voting started, reports came in of violent incidents at polling stations in which at least 24 were reported to have been killed.

Two main presidential candidates:

Muhammadu Buhari, All Progressives Congress (APC), Muslim northerner, ex-military ruler, fourth presidential bid

Goodluck Jonathan, People's Democratic Party (PDP), Christian southerner, incumbent president, second-term bid

Years of military rule ended in 1999 and the PDP has been in power ever since

Nigeria is Africa's largest economy and leading oil producer

With a population of more than 170m, it is also Africa's most populous nation (ANA)

FA/ANA/28 March 2015----------