KABUL - Afghan election officials on Friday defended plans to open more polling centers for next week's presidential run-off despite fears not enough is being done to prevent a repeat of the fraud which marred the first round.

Security is also a major concern ahead of the November 7 run-off, which the Taliban have vowed to disrupt, underlined by a suicide attack this week on a guest-house used by the United Nations in which five foreign U.N. staff were killed.

Western officials have already described as disturbing plans for the run-off, which both Kabul and Washington hope will end weeks of political uncertainty.

It also comes as U.S. President Barack Obama weighs whether to send thousands more troops to Afghanistan, where violence this year has reached its worst levels since the Taliban were ousted by U.S.-backed Afghan forces in 2001.

The run-off between President Hamid Karzai and his main rival, former foreign minister Abdullah Abdullah, was triggered by a U.N.-led fraud investigation into the first round of voting which found widespread fraud in favor of Karzai.

With little time to organize the run-off, security concerns keeping voter turn-out down in the first round and winter fast approaching, election officials last week said fewer polling centers would be open for the run-off than in August.

But the government-appointed Independent Election Commission (IEC) now says the number of polling centers would increase slightly, largely because of better security in former Taliban strongholds in the south where U.S., British and Afghan forces have been fighting major offensives.

The number of polling stations is not too many ... it is because of better security in certain areas, Daoud Ali Najafi, Chief Electoral Officer for Afghanistan, told Reuters.

Western officials have expressed fears increasing the number of polling centers would raise rather than lessen the risk of fraud.

Najafi said 6,315 polling centers were set up in the first round, although many never opened because of poor security and Taliban threats. He said authorities were setting up 6,322 centers for the run-off, mainly reflecting better security in parts of southern Helmand province.

In the first round ... we had more (polling centers) than we needed. But there are seven more centers in Helmand in districts that have been secured since then and they will open for the second round, Najafi said.

Whether the polling centers would actually open on November 7 would depend on security at the time, he said.

SECURITY FEARS

Karzai, who is expected to win the run-off, assured U.N. Secretary-General Ban Ki-Moon in a telephone call overnight that the United Nations would provide better security for U.N. staff after Wednesday's attack.

President Karzai assured the U.N Secretary-General that Afghanistan ... will do everything to provide proper security to all U.N. staff in the country and better security measures for U.N installations, said a statement from the president's palace.

Ban said the United Nations, which has been operating in Afghanistan for almost 60 years, will beef up its security. U.N. officials in Kabul have said they will continue to support the run-off.
The Taliban have said the guest-house was targeted because of the U.N. role in helping organize the vote.

Sporadic attacks took place across Afghanistan during the first round but failed to disrupt the process entirely.

In a further sign of escalating violence, eight civilians were killed when their vehicle was hit by a roadside bomb in eastern Nangarhar province on Friday morning, the Interior Ministry said in a statement.

Villagers said the target of the attack appeared to be a tribal elder who was a passenger in the car.

On Thursday four civilians were killed when their vehicle hit a roadside in southern Kandahar province, the Interior Ministry said.

(Additional reporting by Louis Charbonneau in at the UNITED NATIONS, Hamid Shalizi in KABUL and Rafiq Sherzad in KHOGIANI; Writing by Golnar Motevalli; Editing by Paul Tait)

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