Women protest against irregularities during last week's state elections in Nigeria's southern city of Warri, in the oil-rich Niger Delta, yesterday. Nigeria holds its presidential election on Saturday amid concern over its validity as a democratic poll and the possible impact on oil supplies of an unclear outcome or violence. - Reuters

ABUJA (Reuters):

Nigeria's opposition charged yesterday that rigging had already begun on the eve of a keenly-watched presidential election, but the authorities denied reports ofdoctored ballots.

The opposition said troops in the northern city of Kaduna had intercepted a truck of ballots in favour of the ruling People's Democratic Party (PDP) 24 hours before the poll, seen as a watershed for both Nigeria and Africa.

In nearby Katsina, opposition parties accused the PDP of marking ballots after taking them to private houses, and of masterminding the arrest of hundreds of opposition sympathisers.

Regional polls last weekend, which gave the PDP a landslide, were marred by widespread abuses.

"Soldiers in Kaduna have intercepted a truck-load of ballot papers, all already thumb-printed for the PDP ahead of Saturday's elections," said Lai Mohammed, spokesman for the Action Congress (AC) party. He said the ballots had been taken to a barracks in Kaduna city.

The electoral commission said in the morning that ballot-tampering could not have occurred because new voting slips were still arriving from abroad after a last-minute change, and had not yet been distributed.

Electoral commissioner Maurice Iwu announced a two-hour delay to 0900 GMT in the start of Saturday's voting, to give more time for ballots to reach the far corners of the vast, chaotic nation, which is Africa's top oil producer.

The election is intended to mark a big step forward for democracy in Africa's most populous country, ushering in the first handover from one elected president to another in a country scarred by three decades of army rule.

But observers witnessed every form of rigging at last Saturday's regional election, and said many of the results did not reflect the will of the people.

A last-minute Supreme Court ruling on Monday has deepened confusion over the election.

The court ruled the election commission acted illegally in disqualifying Atiku Abubakar, President Olusegun Obasanjo's estranged deputy and AC candidate. He was then reinstated.