Authorities in the Russian Far East on Thursday cancelled the result of a runoff governorship vote in an unprecedented move after claims of vote-rigging in favour of a candidate backed by President Vladimir Putin triggered protests.
A local electoral commission took the decision after Russia's election chief Ella Pamfilova on Wednesday recommended re-running the vote.
The crisis erupted in the Far Eastern region of Primorsky Krai where an opposition candidate accused a ruling party representative endorsed by Putin of "stealing" his victory in the vote last Sunday.
Communist Party candidate Andrei Ishchenko, 37, seemed poised to become the next governor of Primorsky Krai until the results suddenly changed overnight allowing his Kremlin-backed rival, Andrei Tarasenko, to claim victory.
Sunday's vote was a second-round runoff after Tarasenko failed to win at least 50 percent of the vote in the first stage.
Tarasenko on Thursday accepted the annulment of the vote.
"There have been too many complaints, everything has to be fair and decent. The cancellation of the vote result is fair," he told Russian media.
The Communist Party had earlier urged authorities to call the race for Ishchenko instead of re-running it.
Communist candidate Ishchenko said he will appeal the election commission's decision in court and that he planned rallies in Vladivostok, the capital of Primorsky Krai.
In Moscow, electoral head Pamfilova welcomed the decision saying "there was no other way out in this situation."
Asked if she can guarantee that the next vote will be fair, she told Interfax news agency: "Now only God can guarantee things."
On Wednesday she said there were "serious violations" in the vote and referred to instances of ballot-stuffing and bribes, but denied that it was rigged in favour of the Putin-backed candidate.
Local authorities are due to set a new date for the vote later this month.
While nearly every election in Russia is marred by claims of vote-rigging, the opposition and ordinary Russians said ballot-stuffing during the far eastern vote was especially brazen.
According to the official results, Tarasenko won 49.55 percent of the vote after a sudden surge, while Ishchenko received 48.06 percent.
That result came despite the Communist Party candidate enjoying a five-point lead when more than 95 percent of votes were counted.
The Kremlin this month suffered election blows in the regions of Khabarovsk, Khakasia and Vladimir, where ruling party candidates failed to win in the first round.