MOSCOW -- Armed Russian men in unmarked military uniforms took up positions at Crimea's main airport in Simferopol early Friday, and there were reports that Russian naval forces had taken control of the military airport in Sevastopol, Moscow's leased base for its Black Sea fleet.
Dozens of rifle-toting men, many of them masked, were patrolling the parking lot and entrance of the Simferopol airport, news agencies in the Russian-dominated Ukrainian territory reported.
Ukraine's acting interior minister, Arsen Avakov, accused Russian nationalist militants of attempting "an armed invasion and occupation," Russia's RIA Novosti news agency reported, citing Avakov's Facebook page.
But Avakov said the situation would be dealt with "on the diplomatic level before armed clashes broke out," RIA Novosti said.
Russia's Black Sea fleet denied involvement in the appearance of armed men at Sevastopol's military airport, the Interfax news agency reported.
Sevastopol airport duty chief Anatoly Rechenko was quoted by UNIAN news agency as saying armed Russian troops were blocking the roads to the military airport, which was closed and its three charter flights scheduled for Friday canceled.
Gunmen representing themselves as "protectors of the Russian people in the Crimea" also appeared on the border between the Crimean republic and mainland Ukraine, a visitor said.
"I saw at least two checkpoints of local Russian residents with arms along the road as I was leaving Ukraine by car this morning," Valery Balayan, a movie director and producer told The Times in a phone interview. "They had Russian flags hoisted over checkpoints."
Crimea has become a flashpoint between Ukraine and Russia since an opposition movement last week forced out President Viktor Yanukovich, who was seen by Ukraine's Russian minority as allied with Moscow and committed to protecting the Russian-speaking community's rights.
Armed men in unmarked uniforms similar to those worn by the men occupying Simferopol airport on Thursday took control of the Crimean Autonomous Republic parliament and another government building. Clashes between pro-Russian demonstrators and Crimea's Ukrainian minority and Tatar populations occurred outside the buildings a day earlier, exposing the region's political and cultural tensions.
The airport deployments were carried out by armed men that Avakov said had been identified as Cossacks, a reconstituted pre-Revolutionary Russian nationalist militia that is not part of Moscow's official defense forces.
Sevastopol airport was not operating, Avakov said. Civilian flights out of Simferopol were operating normally, Western news agencies reported from the scene at Crimea's main transportation hub.
Avakov said about 100 men who identified themselves as Cossacks had attempted to take over the Simferopol airport late Thursday but were repelled by Ukrainian police. Another 119 men in uniforms that appeared to be Russian military camouflage but without insignia showed up at 1:30 a.m. and settled in at the airport's restaurant.
The soldiers refused to respond to queries from Interior Ministry officers about whether they were soldiers and if they had permission to be in the airport, according to Avakov's statement as reported by RIA Novosti.
“I assess what is happening as an armed invasion and occupation. It is in violation of all international treaties and norms. This is a direct provocation to armed bloodshed on the territory of a sovereign state,” Avakov said.
Acting Ukrainian President Oleksandr Turchynov had warned Thursday that Russian military in Crimea should remain inside their bases to avoid an escalation of tensions on the peninsula.
"Any movement, particularly with weapons, outside official residences regulated by our agreement will be interpreted by us as military aggression,” Turchynov said.
The BBC showed video of the armed men smoking and patrolling the Simferopol airport parking lot as wary travelers went about their business. The British broadcaster showed video of one unidentified gunman saying they were there "to ensure general order" and to prevent "radicals from Kiev" intervening in the Crimean standoff.
Ukraine's UNIAN news agency quoted Simferopol airport spokesman Igor Stratilati as saying the gunmen had left by late morning, although other news agencies said the armed men were still on site.
The Russian minority in eastern Ukraine has reacted with alarm at the sudden turnover of political power in the capital, Kiev. A three-month protest movement in demand of Yanukovich's resignation flared into deadly clashes last week, leaving 82 protesters and police dead and forcing Yanukovich to sign a European Union-brokered agreement to cease fighting and submit to new elections.
Yanukovich, who has taken refuge in Russia, provoked the standoff in late November when he refused to sign an association agreement with the EU that would have boosted trade ties between Ukraine and the West, instead announcing that the country would stay integrated with Russia's economy.
Times staff writers Williams reported from Moscow and Loiko from Kiev.
Copyright © 2014, Los Angeles Times