Taliban militants cut off the ink-stained fingers of two Afghan voters in the militant south during the presidential election, the country's top election monitoring group said Saturday.

Two voters who had dipped their index fingers in purple ink — a fraud prevention measure — were attacked in Kandahar province shortly after voting Thursday, said Nader Nadery, the head of the Free and Fair Election Foundation of Afghanistan. Kandahar is the spiritual birthplace of the Taliban.

Rumors that militants would cut off voters' ink-stained fingers spread before the vote. A Taliban spokesman had said militants would not carry out such attacks, but the Taliban is a loose organization of individual commanders who could carry out the threat on their own.

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 where President Hamid Karzai was expected to run strongly among his fellow Pashtuns. At least 26 Afghan civilians and security forces died in dozens of militant attacks.

If results show that more people voted in the north than the south, "then we will have an issue," Nadery said.

Fewer votes in the south would harm the chances of Karzai to win a second five-year term, and increase the chances that his top challenger, former Foreign Minster Abdullah Abdullah, could pull off an upset.

If neither candidate gets 50 percent in the first round, they will go to a second round runoff. Initial preliminary results won't be announced until Tuesday, and final results won't be certified until mid-September.

Nadery said his group saw widespread problems of election officials who were not impartial and were pressuring people to vote for certain candidates. Election monitors also saw voters carrying boxes of voter cards — so many votes could be cast — to polling sites, he said.

Both Karzai and Abdullah claimed to be ahead in early vote counting. Karzai's campaign insisted Friday he would have enough votes to avoid a runoff. Abdullah countered that he was leading but suspected there would be a runoff.

Election officials called on the candidates to refrain from such claims, which could delay the formation of a new government.

Officials of Afghan and international monitoring teams agreed it was too early to say who won or to know whether fraud was extensive enough to affect the outcome.

The European Union on Saturday said the election represented a "victory for democracy," and that the vote count must be carried out in a transparent manner. The EU has deployed teams of election monitors.

The EU's external affairs commissioner, Benita Ferrero-Waldner, said a fair vote is necessary to ensure that elected candidates enjoy public support.

President Barack Obama congratulated the Afghan people Friday for pulling off the election in the midst of violent intimidation.