Oleksandr Turchynov, who stepped in as president after Viktor Yanukovych fled Kiev last weekend, said Friday that the Ukrainian military will fulfill its duty but will not be drawn into provocations.
Heavily armed men in military uniform arrived at strategic facilities in Crimea, prompting Ukraine to accuse Russia of "military invasion and occupation" — a claim that brought an alarming new dimension to the crisis.
Russia kept silent on claims of military intervention, even as it maintained its hard-line stance on protecting ethnic Russians in Crimea, a territory that has played a symbolic role in its national identity.
Earlier Friday, Ukraine's fugitive president resurfaced in Russia to deliver a defiant condemnation of what he called a "bandit coup" in Kiev.
Yanukovych struck a tone both of bluster and caution — vowing to "keep fighting for the future of Ukraine," while ruling out seeking Russian military help.
"Any military action in this situation is unacceptable," he told reporters in the southern city of Rostov-on-Don near the border with Ukraine. In his closing remarks, seeking to make a firm point, Yanukovych tried — and failed — to break a pen.
Ukraine's population is divided in loyalties between Russia and the West, with much of western Ukraineadvocating closer ties with the European Union while eastern and southern regions look to Russia for support.
Crimea, a southeastern peninsula of Ukraine that has semi-autonomous status, was seized by Russian forces in the 18th century under Catherine the Great, and was once the crown jewel in Russian and then Soviet empires.
It became part of Ukraine in 1954 when Soviet leader Nikita Khrushchev transferred jurisdiction from Russia, a move that was a mere formality until the 1991 Soviet collapse meant Crimea landed in an independent Ukraine.
Mills reported from Rostov-on-Don; AP reporters Ivan Sekretarev in Simferopol, Ukraine; Maria Danilova and Karl Ritter in Kiev; Nataliya Vasilyeva in Moscow; and Geir Moulson in Berlin contributed to this report.
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