KABUL, Afghanistan — President Hamid Karzai's leading challenger accused him Saturday of using the Afghan state to "rig" last week's presidential election and detailed allegations of cheating by government officials.
Abdullah Abdullah, once Karzai's foreign minister, said he was in contact with other campaigns to explore the possibility of a coalition candidacy in case none of the 36 candidates won enough votes in Thursday's ballot to avoid a runoff, probably in October.
The accusations, which Karzai's spokesman denied, are the most direct Abdullah has made against the incumbent in a contest that likely has weeks to go before a winner is proclaimed. Both Abdullah and Karzai claim they are in the lead based on reports from campaign pollwatchers monitoring the count.
Officials of Abdullah's campaign have alleged fraud in several southern provinces where the insurgency is strongest and Karzai had been expected to run strong. Abdullah has called for calm and says grievances should be resolved through the country's Electoral Complaints Commission.
Abdullah said during an interview that government officials in Kandahar and Ghazni provinces, including a provincial police chief and a No. 2 provincial election official, stuffed ballot boxes in Karzai's favor in six districts. He also said his monitors were prevented from entering several voting sites.
Karzai's campaign spokesman Waheed Omar claimed the president's camp had submitted its own reports of fraud allegedly committed by Abdullah's followers to the election complaints commission.
Millions of Afghans voted in the country's second-ever direct presidential election, although Taliban threats and attacks appeared to hold down the turnout, especially in the south. Election observers have said the voting process was mostly credible.
Preliminary results will not be released until Tuesday.
Taliban militants carried out dozens of attacks on election day, violence that killed 26 Afghan civilians and security forces.
In a harrowing attack on voting day, Taliban militants cut off the ink-stained fingers of two voters in Kandahar province shortly after the victims cast ballots.