Footage filmed during Russia's presidential election appear to show ballot boxes being stuffed with papers.
Officials claim that the votes cast in the republic of Dagestan will be annulled after an online outcry and allegations of corruption.
Ballots were filmed across the country in response to furious protests over practices during 2011's State Duma elections that saw Putin's United Russia party narrowly cling to a majority.
Several undercover recordings showed corrupt practices during the elections, which the government pledged to stamp out.
The Dagestan footage appears to show a number of voters walking to the ballot boxes with several papers. They then post them one after another while standing outside the camera's view.
Another piece of footage showed the lights in a Dagestan count turned off, which activists claimed was an attempt to see the camera's taken out of action to cover ballot stuffing.
Russia's Central Commission claims it has submitted the materials on the incident to the Investigative Committee and Prosecutor's office, while Stanislav Govorukhin, head of Putin's election headquarters, said they would appeal against the republic's results.
He told a media conference that it was "more likely" that the handfuls of papers represented a transfer from a small ballot box.