Because of Crimea's staunch pro-Russia sentiments, analysts warn that the country could break apart if politicians in Kiev continue their push toward NATO and the West.
"Most threats from Ukraine don't come from outside, but from inside," said Vladimir Kornilov, a political scientist in Kiev. "Ukraine is living on its own volcano."
Critics accuse the Black Sea Fleet of deliberately exacerbating the tension.
"All the anti-Ukrainian, pro-Russia blocs are closely tied to the Black Sea Fleet," said Miroslav Mamchak, the snowy-haired chief of a group called the Ukrainian Community of Sevastopol. "They struggle against the Ukrainian language. They support the separatists."
Mamchak is a rare voice of Ukrainian nationalism here. He says that he has received death threats, and that Russian loyalists plastered the town with his picture under the slogan, "I'm a traitor to Russia."
Black Sea Fleet officials deny any political tampering. But many Ukrainians worry that Moscow is stealthily working to stir up separatist sentiment. There have been reports that Russia has quietly begun to grant passports to some residents; Russian officials say it's not true.
Powerful Moscow Mayor Yuri M. Luzhkov, who has been banned from Ukraine for his rhetoric on Crimea, has said the region "doesn't belong" to Ukraine.
Moscow and Sevastopol have long had close ties, and the Moscow city government has built schools and apartments in the Ukrainian city. One opulent school is decorated with stained glass depictions of Moscow, and a university is affiliated with Moscow State University.
Pro-Moscow residents regard Mamchak's political organization as part of a Kiev-backed effort at "ethnocide."
Many people here complain about the mandatory teaching of the Ukrainian language in schools and its use in the media and for government paperwork. Pro-Russia leaders also accuse the Ukrainian government of slowly moving people into the region from other parts of the country and installing pro-Kiev leaders in the city government.
"Faster, faster, faster to make everybody a Ukrainian," said Raisa Telyatnikova, head of the Russian Community of Sevastopol. "They want to completely distance us from our historical motherland, Russia, and turn it into an alien state. . . . They want to change the ethnic composition and break the spirit of Sevastopol."
