People in Crimea took to the polls on Sunday for a referendum on breaking away from Ukraine to join Russia that has precipitated a Cold War-style security crisis on Europe's eastern frontier.
Ukraine's new government and most of the international community except Russia have said they will not recognise a result expected to be overwhelmingly in favour of immediate secession.
Some 1.5 million people are called to vote on the diamond-shaped Black Sea peninsula, which is mostly inhabited by ethnic Russians and has been seized by Russian forces over the past month.
AFP reporters saw voters cast their ballots in the regional capital Simferopol, the naval base of Sevastopol and Bakhchysaray -- the hub of the Muslim Tatar community, which is urging a boycott.
"We have waited years for this moment," said 71-year-old Ivan Konstantinovich, who raised his hands in victory after voting in Bakhchysaray.
"Everyone will vote for Russia," he said.
Crimea says foreign observers are monitoring the vote but the Organisation for Security and Co-operation in Europe (OSCE) is not because it needs to be invited by national governments.
OSCE military observers aiming to defuse tensions have been prevented from entering Crimea, which is at the centre of the worst East-West confrontation since the fall of the Berlin Wall in 1989.
Voters can choose to become part of Russia or retain more autonomy but stay in Ukraine -- a vote for the status quo is not an option.
Preliminary results are expected soon after polls close at 1800 GMT and Russian flags are already being handed out in the streets in Sevastopol.
Preparations to become part of the Russian Federation -- a process that could take months -- are to begin this week if the people vote for Moscow.
Rehearsals for the big day have included a show by Cossack troops and the slogan "We are in Russia!" beamed onto the government building in Simferopol, leaving no doubt as to the expected outcome.
Pro-Russia authorities and Moscow say the referendum is an example of self-determination like Kosovo's decision to leave Serbia but Washington says the vote cannot be democratic because it is taking place "under the barrel of a gun".
Ukraine's new government fears the referendum is part of a plan by Moscow to stir up a wider rebellion across mostly Russian-speaking parts of eastern Ukraine to justify an invasion.
Three activists have been killed in the eastern cities of Donetsk and Kharkiv in the run-up to the Crimea referendum and supporters of Russia have called for similar separatist polls to be held in other Ukrainian regions.
Russian troops and pro-Moscow militias took control of the strategic peninsula soon after the Kremlin-backed Ukrainian president Viktor Yanukovych fled Kiev last month in the wake of three months of deadly protests against his rule.
Russian lawmakers have also given the go-ahead for President Vladimir Putin to invade Ukraine when he wants, citing the need to defend ethnic Russians against ultra-nationalist radicals.
Ukrainian military bases in the region -- also home to Russia's Black Sea Fleet since the 18th century -- are surrounded by militias but there has been no armed Russia-Ukraine armed confrontation so far.
There have however been several attacks on journalists and pro-unity activists condemned by Amnesty International as "extremely worrying".
It is also unclear what will happen to the thousands of Ukrainian military personnel currently based in Crimea after the secession vote.
Ukraine is on full combat alert and on the eve of the vote it accused Russian forces of seizing a village just outside Crimea, saying: "Ukraine reserves the right to use all necessary measures to stop the military invasion by Russia".
The diplomatic wrangling and brinksmanship over Crimea have been startling, including a confrontation at the United Nations Security Council in which Ukrainian Prime Minister Arseniy Yatsenyuk asked: "Do the Russians want war?"
Successive rounds of negotiations between US Secretary of State John Kerry and his Russian counterpart Sergei Lavrov have failed and Kerry appeared to break diplomatic protocol by not showing up for planned talks in Moscow.
While the West has been powerless to stop annexation, Russia faces a painful round of sanctions against top officials that Washington and EU nations are set to unveil on Monday and it could be ostracised or even ejected from the Group of Eight leading world powers.
Local authorities are calling this a "Crimean Spring" but many Crimeans are simply confused and concerned about a possible legal vacuum and economic turmoil in their region.
"Whether we stay with Ukraine or go with Russia, it's understandable that people are concerned," said Aleksiy Yefremov, head of the student association "New People of Crimea".
"We do not have enough information. Do we listen to officials in Kiev or to the local authorities?"
One immediate concern is about the availability of cash and there have been long queues outside banks with Crimeans rushing to take their money out.
Crimea would not automatically join Russia after the vote and the local pro-Moscow prime minister Sergiy Aksyonov said it could take "a year maximum".
Ukraine's government has said Crimea cannot survive on its own since it depends on electricity, energy and water supplies from the mainland.
"We are ready to sit without electricity, without water... We're afraid of nothing and we want a historic choice," Aksyonov said earlier.
Aksyonov has assured residents that the region can manage on its own with assistance only from Moscow.