Pro-Russian protesters and Tatars have clashed over the future of Crimea
In the aftermath of the revolution in Kiev - in which pro-Western Ukrainians ousted President Viktor Yanukovych - the focus has shifted to the southern region of Crimea where Russia has deployed troops, triggering a call for reservists across Ukraine and a full-blown international crisis.
Why has Crimea become a flashpoint?
Crimea is a centre of pro-Russian sentiment, which can spill into separatism. The region - a peninsula on Ukraine's Black Sea coast - has 2.3 million people, most of whom identify themselves as ethnic Russians and speak Russian.
The region voted heavily for Viktor Yanukovych in the 2010 presidential election, and many people there believe he is the victim of a coup - leading to attempts by separatists in Crimea's parliament to push for a vote on whether it should leave Ukraine.
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