KIEV, UKRAINE (CBS) - Russian military were blocking a Ukrainian military airport in the Black Sea port of Sevastopol in Crimea near the Russian naval base while unidentified armed men were patrolling another airport serving the regional capital, Ukraine's new Interior Minister Arsen Avakov said on Friday.
No violence was reported, and flights continued to operate at the airport serving Simferopol, the regional capital. It was not immediately clear whether the airport in Sevastopol, owned by the Ukrainian defense ministry, was open but there are no scheduled services to the facility.
The Russian foreign ministry refused to comment while a spokesman for the Russian defense ministry also had no comment.
Avakov wrote in a Facebook post that the Belbek international airport in Sevastopol was blocked by military units of the Russian navy.
"I can only describe this as a military invasion and occupation," Avakov said.
Ukraine's Parliament, meanwhile, adopted a resolution calling for a U.N. Security Council meeting on the nation's crisis and demanding that Russia halt steps which it says are aimed against Ukraine's sovereignty and territorial integrity.
Early on Friday, dozens of armed men in military uniforms without markings were seen patrolling the airport in Simferopol, the capital of Crimea.
An Associated Press photographer saw military men armed with assault rifles Friday morning patrolling the airport. The men, who were wearing uniforms without any insignia, refused to talk to journalists, and it was not immediately clear who they were.
On Thursday, masked gunmen with rocket-propelled grenades and sniper rifles seized the parliament and government offices in Simferopol and raised the Russian flag over the parliament building.
The events in the Crimea region have heightened tensions with neighboring Russia. It scrambled fighter jets on Thursday to patrol borders in the first stirrings of a potentially dangerous confrontation reminiscent of Cold War brinksmanship.
U.S. officials are closely monitoring Russia's military movements near Ukraine's border, reported CBS News correspondent David Martin. So far, it appears to be just an exercise as the Russians say, but that war gaming so close to the border could give Russia a rolling start to push into Ukraine, with little or no warning, and Martin says that is what concerns officials like U.S. Secretary of Defense Chuck Hagel.
In spite of the concern, Martin said the U.S. is also trying to avoid any acts which could raise the tensions further, and according to the top American commander in Europe, NATO is not planning for any military reaction to a Russian intervention in Ukraine.
Russia also has granted shelter to Ukraine's fugitive president, Viktor Yanukovych, after recent deadly protests in Kiev swept in a new government.
Yanukovych has a news conference scheduled Friday in Russia's south near the Ukrainian border. He has not been seen publicly since Saturday, and he declared Thursday in a statement that he remains Ukraine's legitimate president.
Ukraine's parliament on Thursday elected a new government led by a pro-Western technocrat who promptly pledged to prevent any national break-up.
Moscow has been sending mixed signals about Ukraine but pledged to respect its territorial integrity. Russian President Vladimir Putin has long dreamed of pulling Ukraine -- a country of 46 million people considered the cradle of Russian civilization -- closer into Moscow's orbit.
For Ukraine's neighbors, the specter of Ukraine breaking up evoked memories of centuries of bloody conflict.
"Regional conflicts begin this way," Polish Foreign Minister Radoslaw Sikorski said Thursday, calling the confrontation "a very dangerous game."
Ukraine's new prime minister, Arseniy Yatsenyuk, on Thursday said the country's future lies in the European Union, but with friendly relations with Russia.
Yatsenyuk insisted the country wouldn't accept the secession of Crimea. The Black Sea territory, he declared, "has been and will be a part of Ukraine."
Oleksandr Turchynov, who stepped in as acting president after Yanukovych's flight, condemned Thursday's assault in Simferopol as a "crime against the government of Ukraine." He warned that any move by Russian troops off of their base in Crimea "will be considered a military aggression."
Ukraine's population is divided in loyalties between Russia and the West. Crimea, which was seized by Russian forces in the 18th century under Catherine the Great, was once the crown jewel in Russian and then Soviet empires. CBS News correspondent Clarissa Ward reported that 60 percent of the population in Crimea are ethnic Russians, and many simply don't identify with the Ukrainian-speaking western parts of the nation, where Kiev sits and from which the recent opposition overthrow sprung.
"We cannot accept the authority in Kiev. We are a different people," Ludmila Milodanova, a pro-Russian protester said on the streets of Simferopol on Thursday. "We will be happy to join Russia. It is our motherland."
Crimea only 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.
The escalating conflict has sent Ukraine's finances plummeting, prompting Western leaders to prepare an emergency financial package.
In a bid to shore up Ukraine's fledgling administration, the International Monetary Fund has said it is "ready to respond" to Ukraine's bid for financial assistance. The European Union is also considering emergency loans for a country that is the chief conduit of Russian natural gas to western Europe.
Ukraine's finance ministry has said it needs $35 billion over the next two years to avoid default.
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