The main challenger to Afghan President Hamid Karzai in last week's elections said on Sunday he had evidence the ballot had been widely rigged.
With counting underway following Thursday's vote, the country is on tenterhooks ahead of an official result - although the start of the Muslim fasting month of Ramadan and a relative lull in violence has helped calm tensions.
An election result respected by the candidates and their supporters is crucial for the country and United States President Barack Obama, who has made stabilising Afghanistan his top foreign policy priority.
On Sunday former foreign minister Abdullah Abdullah, who was given a fighting chance of pushing the election to a second round, said he had evidence of widespread rigging.
"The initial reports we are receiving are alarming," he said.
"There might have been thousands of violations throughout the country, no doubt about it."
In a separate news briefing, the country's election watchdog said it was dealing with scores of complaints, but there was no sign they would directly affect the result. Read more here ...