MOSCOW-Professional gun handling, well-trained maneuvers, and military-spec arms are among the reasons NATO's top commander says the uprisings in eastern Ukraine are clearly "being carried out at the direction of Russia."

In a blog post entitled "Who are the men behind the masks?" the Supreme Allied Commander in Europe, Gen. Philip Breedlove, offered the most detailed Western evidence to date that, despite Russia's claims that the unrest there is an organic, local movement, it was instead the work of Russian troops posing as locals that orchestrated the apparently coordinated takeover of government buildings in eastern Ukraine that has plunged the fragile country into chaos.

"The pro-Russian 'activists' in eastern Ukraine exhibit tell-tale military training and equipment and work together in a way that is consistent with troops who are part of a long-standing unit, not spontaneously stood up from a local militia," Breedlove wrote.

He specifically cited how the forces handled their weapons, used tear gas and stun grenades, and even how they man checkpoints as evidence that the troops are well-trained, not a civilian mob.

"The way these forces target government buildings, hit them in coordinated strikes and quickly secure the surrounding area with roadblocks and barricades is similar to what we've seen in Crimea. Again, indicative of a professional military force, acting under direction and leadership, not a spontaneous militia," Breedlove wrote.

His comments confirmed what US officials have privately told ABC News, that a well-oiled team of elite troops appeared to storm the building ahead of the local mob. That team did the heavy lifting, seizing the buildings before melting back into the population and leaving the buildings in control of the pro-Russian crowd.

It's a textbook example, the officials said, of the military art of deception that Russia calls "maskirovka," or masking their appearance to blend in with local forces. The Russians have historically been very good at it and are proud of their capabilities. Last year, Russian state-run television news aired a story about the elite teams that train for exactly this kind of cloaked missions abroad.

Russian President Vladimir Putin on Thursday again vigorously denied Western claims that Russian forces were operating in eastern Ukraine. But he also finally confirmed what had long been suspected and that he had repeatedly denied: that the well-armed forces with no insignia on their uniforms that took control of Crimea last month were in fact Russian troops.

Breedlove suggested that was reason to doubt Putin's denials about Russian military presence in eastern Ukraine.

In recent days US officials have also circulated unconfirmed photos of forces in Ukraine that appear to show them armed with Russian military-issue weapons. ABC News reporters in Ukraine also spotted similar equipment on the separatist fighters, including rocket-propelled grenade launchers which appeared to be brand new.

Breedlove also cited this as evidence of Russian meddling.

"The weapons and equipment they carry are primarily Russian army issue. This is not the kind of equipment that civilians would be likely to be able to get their hands on in large numbers," he wrote on his blog.

Members of the militias have insisted to journalists for days that they are locals and are now instructed or bankrolled by the Kremlin. Many, they say, are former riot police or army veterans.

Still, US officials point to leaked calls, like one released this week by Ukraine's security services, known as the SBU, that claims to show evidence of Russia guiding the separatists. The SBU also claimed to have captured several Russians it alleges are agents sent to foment unrest in Ukraine. Those claims have been impossible to verify.

"Any one of the points above taken alone would not be enough to come to a conclusion on this issue, but taken in the aggregate, the story is clear," Breedlove wrote on his blog.