The Nigerian elections continued for a second day, after technical problems hit around 300 polling stations.
About 300 out of around 150,000 were affected by the glitch, which left voters, including President Goodluck Jonathan, unable to cast their vote.
"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.
Polling stations were also hit by attacks from unknown gunmen.
However, Mr Jonathan told the BBC's Peter Okwoche that most of the violence in Gombe was not directly related to the elections.
"The war against terrorists is going on, voting or no voting," he said. "There was a conflict, kind of a crossfire, between soldiers and terrorists that had nothing to do with the elections."