Russia launched referendums on Friday aimed at annexing four occupied regions of Ukraine, drawing condemnation from Kyiv and Western nations who dismissed the votes as a sham and pledged not to recognise their results.
Ukrainian officials said people were banned from leaving some occupied areas until the four-day vote was over, armed groups were going into homes, and employees were threatened with the sack if they did not participate.
Ukrainian President Volodymyr Zelenskiy said in a nightly address that the votes would be "unequivocally condemned" by the world, along with the mobilisation Russia began this week, including in Crimea and other areas of Ukraine occupied by Russia.
"These are not just crimes against international law and Ukrainian law, these are crimes against specific people, against a nation," Zelenskiy said.
The votes on becoming part of Russia were hastily-organised after Ukraine recaptured large swathes of the northeast in a counter-offensive earlier this month.
With Russian President Vladimir Putin also announcing a military draft this week to enlist 300,000 troops to fight in Ukraine, the Kremlin appears to be trying to regain the upper hand in the grinding conflict since its Feb 24 invasion.
Zelenskiy also addressed people in parts of Ukraine occupied by Russia, and said they should resist efforts to mobilise them to fight.
"Hide from Russian mobilisation in any way you can. Avoid draft orders. Try to move to the territory of free Ukraine," he said, urging those who did end up in the Russian armed forces to "sabotage," "interfere" and pass on intelligence to Ukraine.
By incorporating the four areas, Moscow could portray attacks to retake them as an attack on Russia itself – potentially using that to justify even a nuclear response.
Putin and other Russian officials have mentioned nuclear weapons as an option in extremis: a terrifying prospect in a war that has already killed tens of thousands of people, uprooted millions and pummelled the global economy.
Voting in the provinces of Luhansk, Donetsk, Kherson and Zaporizhzhia in the east and southeast, representing about 15% of Ukrainian territory, was due to run from Friday to Tuesday.
"Today, the best thing for the people of Kherson would be not to open their doors," said Yuriy Sobolevsky, the displaced first deputy council chairman of Kherson region.
In the Donetsk region, the turnout on Friday was 23.6%, Tass cited a local official as saying. Over 20.5% of voters eligible to vote in the Zaporizhzhia region and 15% of those in the Kherson region voted on Friday, Russia's Interfax news agency reported, citing local electoral officials.
"In our view, that's enough for the first day of voting," the head of Kherson's Russian-installed election commission, Marina Zakharova, was quoted as saying.
Polling stations were also set up in Moscow, for residents of those regions now living in Russia. Flag-waving government supporters attended rallies in Moscow and St Petersburg in favour of the referendums and the war effort.