"To critics, especially in Ukraine, the Kremlin’s hand is seen in many of the most disturbing turns in the unfolding situation, including the visits by Russian lawmakers; reports of handing out Russian passports to Crimea’s citizens, as happened in Georgia’s breakaway regions of South Ossetia and Abkhazia; and the mysterious seizure of the Parliament building in Crimea. They see the downward spiraling of events as evidence that Mr. Putin intends to splinter the country and retake Crimea as Russian territory." (via nytimes)
Here’s a short run down on what Crimea is all about, past and present.
So far the Parliament and most of the airport have been taken over by elements affiliated with Russia in some way.
edit:airport situation is unclear