Independent Election Commission (IEC) director Ziaulhaq Amarkhil said on Wednesday that the results would be delayed until at least Saturday.

Committed to determining results that reflect the will of Afghan voters, the IEC is conducting thorough investigations of all irregularities, IEC said in a press release.

While these investigations have delayed the process slightly, they are critical to the accuracy and integrity of final results,” it added.

Hundreds of serious fraud allegations are reportedly being investigated.

The latest partial results put former foreign minister Abdullah Abdullah in the lead with 44.4 percent ahead of his rival Ashraf Ghani with 33.2 percent as more than half of the votes were counted.

Afghans will have to go to the polls in a runoff on May 28, if no candidate wins at least 50 percent of the vote.

An estimated seven million Afghans went to the polls on April 5 to choose a successor to President Hamid Karzai who has been in office for two terms.