In the southern Afghan district of Shorabak, the tribesmen gathered shortly before last month’s presidential election to discuss which candidate they would back. After a debate they chose to endorse Abdullah Abdullah, President Hamid Karzai’s leading opponent.

The tribal leaders prepared to deliver a landslide for Abdullah – but it never happened. They claim Ahmed Wali Karzai, the president’s brother and leader of the Kandahar provincial council, detained the local governor and closed all the district’s 46 polling sites on election day.

The ballot boxes were taken back to the district headquarters where, tribal leaders allege, they were stuffed with ballots by local policemen. A total of 23,900 ballots were finally sent off to Kabul, the capital – every one of them a vote for Karzai.

The alleged fraud, which Ahmed Wali Karzai denies, was the most blatant example among hundreds of incidents that have threatened to make a mockery of the election.

The sheer scale and audacity of the cheating, which includes supposedly “state-sponsored” ballot-stuffing, vote burning, intimidation and the closure of polling stations in antigovernment areas, has overwhelmed the country’s fledgling Electoral Complaints Commission.

Its staff are battling with more than 2,600 reports of vote-rigging, including at least 650 deemed serious enough “materially” to influence the result.

“This is a blatant violation of the procedure and I think it is stealing in daylight,” Abdullah said yesterday.

His aides say privately that if Karzai wins the 50.1% of votes needed for victory in the first round, they won’t accept the result. Abdullah said he intended to use all legal means to challenge any Karzai victory; his supporters talked menacingly of “Iran-style protests with Kalashnikovs”.

In the Spin Boldak district in the south of the country, the fifth-ranked candidate, Mirwais Yasini, accused pro-Karzai agents of taking out his votes and burning them.

“Democracy is dead in Afghanistan,” he said. “It’s buried. I’m not even bothering to get my results any more because it’s completely rigged. It’s completely biased.”

In the southern province of Oruzgan, pro-Karzai staff tried to bar election observers from entering the polling stations. Abdul Raziq waited three hours outside one station in Tarin Kowt, while election officials questioned his credentials as an observer. He watched 60 to 80 voters go into the Sayed Al-Khan high school, while he argued with the supposedly independent officials.

“Finally, when they let me in, I saw all the ballot boxes were full,” he said. He had arrived at 8am, an hour after the polls opened. “No one was voting because there were rockets, but when I went in, there were eight boxes, all of them full of votes.”

Sher Mohammed Khan, a tribal elder from Oruzgan and an Abdullah supporter, said three of his observers were arrested. “In Derawut district the police chief, Omar Khan, told observers not to come near the polling stations. His henchmen threatened to kill anyone who tried to get in,” he said.

Insecurity in Kandahar and Helmand stopped election observers from visiting all but a handful of polling sites. The country’s Independent Election Commission (IEC), which is counting the votes, is supposed to spot substantial irregularities.

Yet in the Kandahar village of Torzai, the results showed that Karzai had won every vote. At four of its eight polling stations, he received exactly 500 votes. At a primary school in Dahani, Helmand, Karzai also won 100% of the votes.

A row within the IEC over what to do with the suspect ballots has held up the announcement of further results for the past four days. Its last tally on Wednesday showed Karzai three points short of his 50.1% target. He may yet face a divisive second round run-off against Abdullah.

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