Ukraine: 'This is a full-scale invasion'

U.S. official says 1,000 Russian troops enter Ukraine

By Victoria Butenko, Laura Smith-Spark and Diana Magnay, CNN

updated 10:59 AM EDT, Thu August 28, 2014

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STORY HIGHLIGHTS

• Lithuania requests an emergency U.N. Security Council meeting on Ukraine
• U.S. official: Intelligence indicates up to 1,000 Russian troops are in southern Ukraine
• Donetsk rebel leader: Up to 4,000 Russians are fighting; some are active servicemen
• U.S. ambassador to Ukraine says Russia is "now directly involved in the fighting"

Kiev, Ukraine (CNN) -- A top Ukrainian army officer said a "full-scale invasion" of his country was under way Thursday, as a U.S. official said up to 1,000 Russian troops had crossed Ukraine's southern border to fight alongside pro-Russian rebels.

U.S. officials said Russian troops were directly involved in the latest fighting, despite Moscow's denials.

Rebels backed by Russian tanks and armored personnel carriers fought Ukrainian forces on two fronts Thursday: southeast of rebel-held Donetsk, and along the nation's southern coast in the town of Novoazovsk, about 12 miles (20 km) from the Russian border, according to Mykhailo Lysenko, the deputy commander of the Ukrainian Donbas battalion.

"This is a full-scale invasion," Lysenko said, referring to the fighting in the south.

Fighting in Ukraine may be spreading

Photos: Crisis in Ukraine

Ukraine: Russians captured in east

Intelligence now indicates that up to 1,000 Russian troops have moved into southern Ukraine with heavy weapons and are fighting there, a U.S. official told CNN Thursday.

Ukraine's National Defense and Security Council said that Russian forces were in full control of Novoazovsk as of Wednesday afternoon.

Russia's military fired Grad rockets into the town and its suburbs before sending in two convoys of tanks and armored personnel carriers from Russia's Rostov region, it said in a statement

"Ukrainian troops were ordered to pull out to save their lives. By late afternoon both Russian convoys had entered the town. Ukraine is now fortifying nearby Mariupol to the west," the NDSC said.

A number of villages in the Novoazovsk, Starobeshiv and Amvrosiiv districts were also seized, it said.

The NDSC also warned that a rebel counterattack is expected in the area where Malaysia Airlines Flight 17 was shot down in July. Ukrainian and Western officials believe it was downed by rebels armed with Russian-made weapons.

Novoazovsk is strategically important because it lies on the main road leading from the Russian border to Ukraine's Crimea region, which Russia annexed in March. Separatist leaders in the Donetsk and Luhansk regions then declared independence from Kiev.

U.N. Security Council to meet

As international concern mounted over the apparent escalation in fighting, Lithuania requested an emergency U.N. Security Council meeting on Ukraine.

UK ambassador to the United Nations Mark Lyall Grant said Russia would be asked to explain why its soldiers are in Ukraine.

U.N. political chief Jeffrey Feltman, who is just back from Ukraine, is expected to give the Security Council an update on the troop situation there.

Ukrainian President Petro Poroshenko and Prime Minister Arseniy Yatsenyuk had earlier called for the U.N. meeting, as well as action by Europe.

The latest flare-up comes despite a meeting between Poroshenko and Russian President Vladimir Putin in Belarus on Tuesday at which some progress appeared to have been made toward finding a diplomatic solution to the crisis.

Ukrainians fight to survive amid siege

Questions return with Russian convoy

Poroshenko canceled a planned trip to Turkey on Thursday "due to sharp aggravation of the situation in Donetsk region ... as Russian troops were brought into Ukraine," a statement from his office said.

In a Cabinet meeting, Yatsenyuk said Russia "has very much increased its military presence in Ukraine" and that tougher measures may be needed to curb Russia's support for the rebels.

"Unfortunately, the sanctions were unhelpful as to de-escalating the situation in Ukraine," he said, referring to the economic sanctions imposed by the United States and European Union against Russian individuals and companies.

Yatsenyuk suggested one way to halt "Russian aggression" could be to freeze all assets and ban all Russian bank transactions until Russia "pulls out all its military, equipment and agents" from Ukraine.

"Vladimir Putin has purposely started a war in Europe. It is impossible to hide from the fact," he said.

U.S. ambassador: Russia is directly involved

U.S. Ambassador to Ukraine Geoffrey Pyatt also said Thursday that Russian soldiers were directly involved in the fighting, alongside the pro-Russia rebels.

"Russian-supplied tanks, armored vehicles, artillery and multiple rocket launchers have been insufficient to defeat Ukraine's armed forces, so now an increasing number of Russian troops are intervening directly in the fighting on Ukrainian territory," he said on Twitter.

"Russia has also sent its newest air defense systems including the SA-22 into eastern Ukraine and is now directly involved in the fighting."

Moscow denies supporting and arming the pro-Russia rebels. It has also repeatedly denied allegations by Kiev that it has sent troops over the border.

A Russian senator and the deputy head of the Committee on Defense and Security in Russia's upper house of Parliament, Evgeny Serebrennikov, dismissed the latest reports of a Russian incursion as untrue.

"We've heard many statements from the government of Ukraine, which turned out to be a lie. What we can see now is just another lie," he said to Russian state news agency RIA Novosti.

Russian lawmaker Leonid Slutsky also accused Kiev of lies, in comments to RIA Novosti.

"I can only say that there's no ground for claims like this, and the junta tries to lay its own fault at someone else's door," he said, referring to the Kiev government.

Moscow regards it as illegitimate because it took charge after Ukraine's pro-Russian President Viktor Yanukovych was ousted in February.

Russian soldiers detained in Ukraine; leaders meet in Minsk

Rebel leader: 3,000 to 4,000 Russians in our ranks

However, the Prime Minister of the self-declared Donetsk People's Republic, Alexander Zakharchenko, acknowledged Thursday that there are current Russian servicemen fighting in the rebels' ranks in eastern Ukraine.

In his statement, televised on state-run Russia 24, Zakharchenko said the rebels have never concealed that many Russians are fighting with them. He said up until now there were 3,000 to 4,000 volunteers, some of whom are retired Russian servicemen.

Zakharchenko went on to reveal that the Russian servicemen currently fighting in their ranks are active, "as they came to us to struggle for our freedom instead of their vacations."

On Tuesday, Ukraine's Security Service said it had detained 10 Russian soldiers in Ukraine.

Russian state media cited a source in the Russian Defense Ministry as saying the soldiers had been patrolling the border and "most likely crossed by accident" at an unmarked point.

The NDSC said Thursday that Ukraine's Security Service detained another Russian serviceman who testified that his unit was supplying heavy military equipment to militants.