Abuja, March 31 (IANS): Nigeria's ruling party on Tuesday staged a protest at the national collation centre for the presidential election, accusing the electoral body of being partial and calling for "a total cancellation of the count".

Led by its agent at the election collation center, Godsday Orubebe, the ruling Peoples Democratic Party (PDP) members staged a half-hour protest and delayed the collation process, Xinhua news agency reported.

Orubebe said the electoral body has ignored the PDP's petitions on alleged voting irregularities in seven northern states, but has accepted a petition from the opposition All Progressives Congress about alleged vote rigging in the southern Rivers state and launched a probe into it.

Orubebe, who mounted the platform and halted the process, said "he would not allow the collation to continue until his party was given a fair hearing".

Nigerian electoral chief, Attahiru Jega, urged the ruling party to leave the national collation centre, as "it is the electoral body's secretariat that such complaints could be directed to".

The collation process continued after the protest was calmed down by officials.

With the collation process already having gone beyond the halfway mark, the winner of Nigeria's presidential election, held during the weekend, is likely to emerge on Tuesday.

Incumbent President Goodluck Jonathan is facing a stiff challenge from ex-military leader Muhammadu Buhari.

Saturday's voting was extended by an additional day in some parts of Nigeria after the delayed arrival of ballot papers and problems with the electronic card reader.

The process was largely peaceful despite some sporadic attacks in southern states, causing deaths and injuries.

Counting of votes started on Sunday but the final counting, which started on Monday, has also spilled into a second day.

Many hope the new leader can address the economic woes caused by falling oil prices and security threats posed by the extremist group Boko Haram.