Voting is to continue in some parts of Nigeria after technical problems during Saturday's presidential election.
The electoral commission postponed voting because of problems with electronic card readers - new technology intended to reduce fraud.
There was also some violence with more than 20 people reportedly killed in attacks by unknown gunmen.
It is expected to be a closely fought election between President Goodluck Jonathan and Muhammadu Buhari.
Mr Jonathan and at least three governors from his ruling party were among those whose biometric details could not be checked by the new devices.
Instead, they had to be processed by hand. Mr Jonathan's Peoples Democratic Party (PDP) called it a "huge national embarrassment" and a "vindication" of their position against the technology.
"There should have been a test-run for a smaller election before deploying it for an election of this magnitude," said Mr Jonathan's presidential campaign spokesman Femi Fani-Kayode.
The electoral commission postponed voting because of problems with electronic card readers - new technology intended to reduce fraud.
There was also some violence with more than 20 people reportedly killed in attacks by unknown gunmen.
It is expected to be a closely fought election between President Goodluck Jonathan and Muhammadu Buhari.
Mr Jonathan and at least three governors from his ruling party were among those whose biometric details could not be checked by the new devices.
Instead, they had to be processed by hand. Mr Jonathan's Peoples Democratic Party (PDP) called it a "huge national embarrassment" and a "vindication" of their position against the technology.
"There should have been a test-run for a smaller election before deploying it for an election of this magnitude," said Mr Jonathan's presidential campaign spokesman Femi Fani-Kayode.
