Vladimir Putin will lead Russia for another six years, after securing an expected victory in the presidential election.
A Russian state exit poll gave him 73.9% of the vote, easily defeating his closest competitor.
The main opposition leader, Alexei Navalny, was barred from the race.
The scale of victory - which had been widely predicted - was a marked increase in his share of the vote from 2012, when he won 64%.
A state exit poll put the turnout at 63.7%, down on 2012. Putin's campaign had hoped for a large turnout, to give him the strongest possible mandate.
Reacting to the exit poll, his campaign team said it was an "incredible victory".
"The percentage that we have just seen speaks for itself. It's a mandate which Putin needs for future decisions, and he has a lot of them to make," a spokesman told Russia's Interfax.
Video recordings from polling stations showed irregularities in a number of towns and cities across Russia. Several showed election officials stuffing boxes with ballot papers.
Early results showed that with just 25% of boxes counted, Putin had almost 73% of the votes.
Exit polls, published as soon as voting ended, showed that Putin's closest opponent, Pavel Grudinin, was only projected to win 11.2%.
Navalny was excluded from the election because of an embezzlement conviction that he said was manufactured by the Kremlin.
In his first reaction to the news, Navalny indicated he had been unable to contain his anger.
"Now is the season of Lent. I took it upon myself never to get angry and not to raise my voice. Oh well, I'll try again next year," he tweeted.
During polling day, independent election monitoring group Golos reported hundreds of irregularities, including:
- Voting papers found in some ballot boxes before polls opened
- Observers were barred from entering some polling stations
- Some people were bussed in amid suspicion of forced voting
- Webcams at polling stations were obstructed by balloons and other obstacles
Videos taken from the election commission's live stream of polling stations also appeared to show some instances of officials stuffing ballots into boxes.
In Dagestan, one election official said he was prevented from doing his job by a crowd of men who blocked the ballot box.
But Ella Pamfilova, head of the Central Electoral Commission, said no serious violations had been registered yet.
"We have analysed and monitored everything we could, everything that has arrived. Thank goodness, it's all rather modest so far," she told a commission meeting while speaking about violations.
She had earlier said that anyone involved in violations would be caught.