Tribal votes intended for Abdullah Abdullah were switched, it is alleged
A row over alleged fraud in the Afghan presidential election has intensified, after a tribe in the south made the most serious claim so far.
The leader of Kandahar's Bareez tribe says that nearly 30,000 votes were cast fraudulently for President Hamid Karzai instead of a challenger.
Mr Karzai's brother, Ahmed Wali Karzai, who heads the Kandahar provincial council, called the claims "baseless".
The Electoral Complaints Commission is probing more than 2,000 fraud claims.
The claims could undermine the legitimacy of the election, which Afghanistan's Western allies see as crucial in their campaign against the Taliban.
Speaking to Daud Qarizadah of the BBC's Persian television service, the Bareez tribal leader, Haji Mohammed Bareez, said that ballot boxes from one district were "stuffed" with fraudulent votes in favour of Mr Karzai.
The tribe believes it has been deprived of its votes and wants a full investigation by the complaints commission, which has the power to discount the votes if they are proved invalid.
Haji Mohammed Bareez: ''No ballot box was sent here''
The tribe decided before the election that it was dissatisfied with the performance of Hamid Karzai and announced it would back Abdullah Abdullah, the former foreign minister and main challenger.
On election day it says its district polling stations were shut down and the ballot boxes brought to district headquarters in Kandahar where they were stuffed with votes in favour of Hamid Karzai.
Mr Bareez said: "Nobody participated in the polling from Shorabak district. No ballot box was brought here. They themselves filled the boxes with ballot papers. As I know 29,823 ballots went into the boxes from this district."
Vote held on 20 August for presidency and provincial councils
Turnout not made official yet but estimated at 40-50%
More than 400 insurgent attacks on polling day, Nato says
More than 2,000 fraud allegations, 600 deemed serious
Final result expected 17 Sept but fraud allegations must be cleared
Hamid Karzai has clear lead over Abdullah Abdullah in presidency race
He said the accusation could be proved with a simple investigation of voter cards and ballot papers.
Ahmed Wali Karzai strongly denied the allegations of fraud.
He told the BBC: "The accusation is baseless and if anyone has any complaints regarding this problem, they should get in touch with the complaints office. I will be more than happy to answer questions."
He said the opposition was making the claims because it had lost the election and was trying to undermine the electoral process.
Haji Mohammed Bareez said that Ahmed Wali Karzai was a powerful figure in Kandahar and his tribe may face threats in the future.
The Karzai camp says most of the allegations lodged with the complaints commission are against Mr Abdullah - a claim he denies.
Mr Abdullah has accused the government and the Independent Election Commission of colluding on fraud.
"With the cooperation of the Election Commission a massive fraud has taken place," he said.
Fraud played down
Because the complaints commission has so many irregularities to investigate - 600 of them serious - our correspondent says final results of the presidential election may not be known until the end of September.
Ballot boxes are stacked ahead of counting in Kandahar on 21 August
A result is scheduled for 17 September but fraud allegations must be cleared before it is made official.
With ballots from 60.3% of polling stations tallied, Mr Karzai has 1,744,428 votes to 1,201,838 for Mr Abdullah, representing a lead of 47.3% to 32.6%.
A candidate needs 50% of the votes to avoid a run-off.
Western powers have played down concerns over fraud although they have stressed a fair outcome is vital.
US envoy to Afghanistan and Pakistan Richard Holbrooke said at a meeting on Afghanistan in Paris on Wednesday that irregularities were normal in any democracy.
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