Nigerian President Goodluck Jonathan's ruling party on Tuesday sought to disrupt the results of the general election, accusing the head of the electoral commission of bias.

Former Niger Delta minister Godsday Orubebe seized the microphone and staged a brief sit-in on the stage as the count was due to resume in the capital Abuja, in front of elections chief Attahiru Jega.

"We have lost confidence in what you are doing," he shouted at Jega. "You are partial. You are selective... We cannot take it. Nigerians will not allow this. We will not leave here."

Orubebe, from the Peoples Democratic Party (PDP), said the party had protested over the election results in the northern states of Kano, Katsina, Kaduna and Jigawa.

Presidential challenger Muhammadu Buhari of the All Progressives Congress (APC) won massively in those states, with between 69 and nearly 93 percent of the vote.

But Orubebe claimed that Jega's Independent National Electoral Commission (INEC) had refused to investigate although they had launched a probe in the southern state of Rivers into alleged PDP vote-rigging.

The claim of irregularities in Rivers came from the APC.

Jega told Orubebe and delegates that he had not received any complaint from the PDP about the northern states.

The protest is a sign of high-running tensions in the closely fought election in which Buhari is about two million votes ahead of Jonathan, with 18 states yet to declare.

The count later resumed.