KABUL (AFP) - Two people were killed in a bomb blast at a rally for Afghan President Hamid Karzai's running mate, the final day of campaigning for landmark elections.
Karzai's candidate for first vice president, Ahmad Zia Massoud, was not injured in the attack at Faizabad, the capital of northern Badakhshan province, said interior ministry spokesman Lutfullah Mashal.
The blast, the latest attack in a spiral of violence, came as the United Nations mission in Afghanistan gave its approval to preparations for the presidential election on Saturday.
The UN's special representative for the troubled country, Jean Arnault, told a news conference that even with "full knowledge of the difficulties", the UN believed the vote would be successful.
"We deem the degree of freedom and fairness adequate to allow the will of the Afghan people as a whole to translate at the polls, and the next president of Afghanistan to claim to represent the nation," he said.
Front-runner and US-backed incumbent President Hamid Karzai pledged to accept defeat if he is beaten.
He was speaking to a crowd of several thousand people at Kabul football stadium, notorious in the past as a public execution arena under the hardline Islamic Taliban regime.
"I have committed that we will respect the vote of the nation. If God willed that I won through the free vote of people I would be happy and accept it," Karzai said.
"And if God willed that someone else won the polls then we should respect the vote of people and we will obey him or her."
The election is the first of its kind in the history of Afghanistan, which has been roiled by conflict for the past 25 years. The Soviet occupation of 1979-89 was followed by a civil war and the fight against the Taliban, who were finally toppled by a US-led invasion in late 2001.
Karzai said it was a "source of great pride that people are expressing themselves through posters and ballots not through guns and bullets".
His upbeat assessment of the election process is not shared by all. Independent analysts say violence and intimidation combine with a lack of education among voters and a shortage of independent monitors to create fertile ground for fraud.
That in turn increases the risk that the winner will not be able to claim an undisputed victory, possibly sparking further violence in a country where regional warlords hold sway outside the capital.
Remnants of the Taliban regime are also waging an insurgency in the south and southeast of the country which has killed hundreds of people this year.
Officials have warned of a possible sharp rise in attacks on Saturday, when up to 10.5 million registered voters go to the polls, with major cities at risk of car-bomb blasts and polling stations under threat of armed assault.
Another 740,000 Afghan refugees in Pakistan have registered to vote and between 400,000 and 600,000 refugees in Iran are expected to cast ballots, giving refugees a possible 10 percent say in the overall vote.
Karzai, 46, who was elected by a council of tribal leaders in June 2002, is widely tipped to win the election.
But former education minister and prominent anti-Taliban fighter Yunus Qanooni, 47, who is seen as Karzai's only serious challenger, also drew a crowd of thousands to a rally in the Kabul stadium Tuesday.
At stake is not only the presidency but the status of the US-led war on terrorism, which has sharply divided the world over the past three years.
A smooth election with an undisputed outcome -- neither of which is guaranteed -- will enable President George W. Bush to claim a victory for his much-maligned foreign policy and to predict a similar outcome for Iraq.