The campaign chief for hardline cleric Ebrahim Raisi said there had been "propaganda actions by certain officials and supporters of the government" in favour of President Hassan Rouhani, who is seeking re-election.
"Such infractions are immoral actions that violate people's rights," said Ali Nikzad.
Iranian election rules state that no one can seek to influence voters once the campaign finishes 24 hours before the polls open.
Another official in Raisi's campaign said there had been 219 infractions so far today, and that not enough ballot papers had been distributed in areas thought to favour Raisi, including his home city of Mashhad.
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The conservative-dominated Guardian Council must validate the results of election.
Meanwhile, officials announced they would keep polling stations open for an extra two hours on Friday evening after many people queued for hours to cast their ballots in the presidential and council elections.
Rouhani, a moderate cleric who has sought to rebuild relations with the world, has been leading in unofficial polls but faces a tough battle for re-election against Raisi, who has called for a tougher approach to the West and more support for the poor.
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