Ukraine war updates: Russia heads to the polls; pro-Ukraine groups continue border assault

This is CNBC's live blog tracking developments on the war in Ukraine.

Russians head to the polls on Friday in a presidential election that is all but certain to grant President Vladimir Putin a fifth term in power.

Voting will take place over three days, though there is no credible opponent to the incumbent leader.

Ukraine's Foreign Ministry on Thursday said that Russian attempts to hold elections in occupied territories or to force regional residents to head to the polls would be "illegal" — a sentiment echoed by NATO chief Jens Stoltenberg in a separate briefing, Reuters reported.

Meanwhile, skirmishes continued Thursday in the Russian border regions of Belgorod and Kursk as three Ukraine-based Russian paramilitary groups — the Freedom of Russia Legion and the Siberia and RDK battalions — seek to break into Russian territory.

The Russian Defense Ministry said on the Telegram messaging app that it repelled another attempted incursion in Belgorod on Thursday, but the Freedom of Russia Legion said the assaults would continue until the region is "completely liberated from the troops of the Putin regime."

Ukraine also shot down 27 Iranian-made drones over seven regions across the country in the early hours of Friday morning, including around the capital, Kyiv's air force claimed.

Two people were killed in a residential building in the central city of Vinnytsia, the regional governor said on Telegram.

Ukraine shot down 27 Iranian-made drones over seven regions across the country in the early hours of Friday morning, including around the capital, the country's air force claimed.

Two people were killed in a residential building in the central city of Vinnytsia, the regional governor said on Telegram.

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