President Hamid Karzai, left, has nearly 50 per cent of the votes in the Aug. 20 election in Afghanistan, while top challenger Abdullah Abdullah has 31 per cent. Nearly three-quarters of polling stations have reported results.

The latest election results from Afghanistan, released as authorities continue to investigate allegations of vote-rigging, show incumbent President Hamid Karzai closing in on victory.

Karzai has 48.6 per cent of the popular vote with 74 per cent of polling stations now reporting, according to results released Sunday. His nearest competitor, Abdullah Abdullah, has 30.7 per cent.

Karzai needs more than 50 per cent to avoid a second round against Abdullah.

Whatever the outcome, the result will likely be disputed.

Ballots from 447 polls in the Aug. 20 vote have been tossed out because of irregularities, election officials said Sunday.

The head of the Independent Election Commission, Daoud Ali Najafi, said it was not yet clear how many votes were affected.

International and Afghan observers have been critical of the vote but have withheld judgment until counting and investigations are complete.

Results won't be finalized until later this month after fraud allegations are investigated.

With files from The Associated Press