Afghan election returns released Tuesday put incumbent Hamid Karzai on course for a single round victory, but a UN-backed watchdog said it had found “clear and convincing evidence of fraud” and ordered a partial recount. The latest data from the Independent Election Commission effectively put Karzai and the Afghan election authorities on a collision course with an international community increasingly sceptical of the outcome of an election it paid for. With 91.6 percent of polling stations counted, the Independent Election Commission reported Karzai ahead with 54.1 percent of the vote to 28.3 percent for his main challenger, former foreign minister Abdullah Abdullah. It was the first time the commission had reported Karzai on course to exceed the 50 percent threshold needed to avoid a second round, and radically alters the calculations of Western diplomats keen to ensure a credible outcome. The results are final only after they are certified by the Electoral Complaints Commission (ECC), a separate body led by a Canadian and mainly appointed by the United Nations. For the first time, it went public with accusations of fraud. “In the course of its investigations, the ECC has found clear and convincing evidence of fraud in a number of polling stations,” the body said in a statement. It ordered the IEC to recount results from polling stations where one candidate received more than 95 percent of the vote or where more votes were cast than the expected maximum of 600. Most of the stations where it found fraud had either a larger than expected number of total votes cast, or a higher than expected proportion cast for a single candidate, it said. The election commission said it was already fighting fraud and had set aside results from more than 600 of the country's 25,000 polling stations because of concerns over irregularities. Some suspicious results posted earlier – including from a village where Karzai received every single vote cast including exactly 500 at each of four separate polling stations – were removed from the commission's web site without explanation. Commission member Daoud Ali Najafi said it could take 2-3 months to comply with the ECC's order, prolonging the state of limbo that the country has been in since last month's poll. A second round, if needed, would be difficult to hold in Afghanistan beyond the end of October because of extreme weather. Hours before the results were released, a suicide car bomber blew up his vehicle outside a NATO military base at Kabul's main airport killing three civilians, the capital's worst attack since the vote and a further sign of deteriorating security. Increased violence in Afghanistan has sapped public support for the war in the United States, which now has about 65,000 troops among the 103,000 foreign troops there.