Story highlights

NEW: NATO officer: Crossing would be latest sign of "Russia's aggression," destabilizing efforts

Ukraine official: Russia's military sent an "armored column" across border into Ukraine

Another Ukrainian official says this includes 32 tanks, 30 KamAZ trucks, 16 howitzers

Russia blasts reports of its troop movements near Ukraine as unfounded and "provocative"

CNN  — 

Amid rising tensions and fresh violence, Ukrainian authorities on Friday accused Russia of sending dozens of its military vehicles into its territory – though the Kremlin have knocked down such reports as unfounded and “provocative.”

At a briefing Friday, Ukrainian defense spokesman Andriy Lysenko said that 32 tanks, 16 D-30 howitzers and 30 KamAZ heavy trucks crossed past a border checkpoint and headed toward the volatile Luhansk region on Thursday.

Another Ukrainian official, Dmytro Tymchuk, alleged the “armored column” consisted of “a battalion tactical group of the Russian Armed Forces,” also according to Ukrinform state news agency.

A NATO military officer said Friday that the alliance – which doesn’t include Ukraine but does include several of its neighbors – is looking into these reports and knows of an increase in Russian troops and equipment on its eastern border.

“If this crossing into Ukraine is confirmed, it would be further evidence of Russia’s aggression and direct involvement in destabilizing Ukraine,” the officer said.

Earlier this week, Canadian Foreign Minister John Baird said that he was “deeply concerned by reports of Russian troops moving closer to the border of Ukraine,” calling such movement “provocative” and “further proof that the Kremlin only seeks to hamper the peace process in Ukraine.”

On Friday, a Russian defense ministry official quoted by the country’s state-run TASS news agency criticized what he called “all such provocative reports aimed at further fueling of tension(s).” The official claimed that a single source had made up the Russian troop movement sightings, reports that have also showed up as “rumors in social networks.”

Wherever the truth lies, southeastern Ukraine itself remains very unsettled – with separatists claiming control over some of the region, despite the efforts of Ukraine’s central government in Kiev.

Those leaders in Kiev have accused Moscow of fomenting the rebellion, in part by aiding the separatists’ militarily and even sending its own troops into Ukraine to take part in the fight. Kremlin officials have consistently denied such claims and accused Kiev authorities of stirring up further unrest.

The violence in the region has ebbed and flowed over the past few months, though it’s never gone away.

In fact, Lysenko told reporters Friday that five Ukrainian soldiers had been killed and 16 more wounded in Donbas over a recent 24-hour stretch.

And Tymchuk said that rebels have been shelling security forces beyond that as well, including 15 recent attacks around Debaltseve, 12 around Donetsk, 10 around Pervomaisky and seven around Luhansk.

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