The foreign ministers of Russia and Ukraine met briefly on the sidelines of a Council of Europe conference in Vienna, Austria's foreign ministry said on Tuesday, to discuss ways to defuse the situation in Ukraine.
"There was a short greeting. They spoke briefly, but not by themselves," a ministry spokesman said of the meeting between Russian Foreign Minister Sergei Lavrov and Ukrainian Acting Foreign Minister Andriy Deshchytsia.
The meeting came late on Monday, after Ukrainian troops had fought pitched gun battles with pro-Russian militias occupying Slovyansk, and the government sent an elite national guard unit to the southern port city of Odessa as Kyiv scrambled to bring much of the country back under the capital’s control.
The Ukrainian Interior Ministry said four officers have been killed and another 30 soldiers injured in the fighting. Gunfire and multiple explosions were heard in and around Slovyansk, a city of 125,000 people that has become the focus of the armed insurgency against the new interim government in Kyiv.
Near Slovyansk on Monday, a Ukrainian military helicopter was shot down, but the pilots survived, Ukraine's Defense Ministry said.
The helicopter, an Mi-24, which came under fire from a heavy machine gun, crashed into a river. The ministry said in a statement its crew members were evacuated to a nearby camp but did not give any details of their conditions. At least three other helicopters have been shot down by pro-Russian armed groups since uprisings began in eastern parts of Ukraine early this year.
Interior Minister Arsen Avakov said on his agency's website that pro-Russian forces were deploying large-caliber weapons and mortars in the eastern region and that there were wounded on both sides.
Government troops were facing about 800 insurgents, he said.
A pro-Russian militia spokesman in Slovyansk said an unspecified number of people had been killed and wounded in the clashes, including a 20-year-old woman killed by a stray bullet.
Both sides indicated that fighting was taking place at several sites around the city.
The tensions in Ukraine also raised concerns in neighboring Moldova, another former Soviet republic, where the government said late Monday it had put its borders on alert.
Moldova's breakaway Trans-Dniester region, located just northwest of Odessa and home to 1,500 Russian troops, is supported by Moscow, and many of its residents sympathize with the pro-Russia insurgency.
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Ukraine is facing its worst crisis in decades as the polarized nation of 46 million tries to decide whether to look toward Europe, as its western regions want to do, or improve ties with Russia, which is favored by the many Russian speakers in the east.
In the last few weeks, anti-government forces have stormed and seized government buildings and police stations in a dozen eastern Ukrainian cities. Authorities in Kyiv — who blame Russia for backing the insurgents — have up to now been largely powerless to react. And since Russia has kept tens of thousands of troops along Ukraine's eastern border and annexed the key Crimean Peninsula in the Black Sea last month, Ukraine's central government fears Russia could invade and grab more territory.
Since the government began trying to take back the buildings late last week, Slovyansk has been kept within a tight security cordon. Movement in and out of the city has almost ground to a halt, causing shortages in basic supplies. Lines have been seen at grocery stores.
The goals of the insurgency are ostensibly geared toward pushing for broader powers of autonomy for the region, but some insurgents favor separatism, and Russia’s annexation of Crimea looms over the entire political and military discussion.
Russia, which the international community has accused of promoting the unrest, has vociferously condemned Ukraine's recent security operations in the east.
NATO Secretary General Anders Fogh Rasmussen, in an interview with Al Jazeera, referred to Russia’s moves in the Ukraine as “modern warfare" and accused the country of attempting to reestablish “a Russian sphere of influence.”
“Unfortunately, I think this Russian behavior will go beyond Crimea, will go beyond Ukraine, and this conflict will last for quite some time,” he said.
As a result, Europe is adapting to a “completely new security situation,” he said, adding that NATO has taken determined steps to strengthen collective defense of its allies.
He warned that if Russia were to intervene further in Ukraine, the international community may impose "broad and deep economic sanctions" that would isolate Russia further.