Moscow [Russia], March 16: Several people have been detained for vandalism at polling stations on the first day of voting in presidential elections, Russian officials say.
Incidents involved green dye being poured into ballot boxes, the boxes being set alight and fireworks being set off inside polling stations, state media reported.
Vladimir Putin is certain to win six more years in office after the vote.
However, officials have called on law enforcement officers to be vigilant.
Voting is taking place in Russia over three days until Sunday. The result is not in doubt as Mr Putin has no credible opponent, however state-run media said that turnout had reached 23% by late afternoon in Moscow.
Most of the incidents were reported at polling stations in Moscow, Voronezh in south Russia, and the region of Karachay-Cherkessia in the north Caucasus, according to state news agency Tass.
BBC Verify has so far verified footage of six incidents across Russia, including a video showing a woman throwing a petrol bomb near a St Petersburg polling station.
Other authenticated videos showed paint being poured into ballot boxes at various polling stations. In one, a woman could be seen pouring bright green liquid into a box in Moscow. Another showed a fire breaking out at a voting booth.
Russia has also enforced the vote in occupied areas of Ukraine - in the small town of Skadovsk, Russian-appointed officials said an improvised device exploded in a rubbish bin in front of a polling station, but no one was hurt.
At least eight people have been arrested although officials have not said if the acts of vandalism were protests against Mr Putin.
According to some videos posted on Telegram, some of of the people who vandalised the ballot boxes reportedly shouted pro-Ukrainian slogans.
The deputy chairman of Russia's Central Election Committee, Nikolay Bulayev, said on Friday there had been five incidents involving liquids being poured into ballot boxes.
Source: Fijian Broadcasting Corporation