Russian Helicopter Fleet Closes in on Crimea - First FootageIBTimes UK

According to news agency Interfax, the helicopters werre said to Mil Mi-24s, large gunships with the capacity to transport troops.

The video footage, shown here, has not been officially verified but Reuters India and Interfax said that Russian helicopter fleets had been seen flying to the region.

The unnamed uploader of the video footage is also believed to be a reporter from the Crimean region.

The film came just hours after two Ukrainian airports were occupied by unidentified militiamen, believed to be Russian military.

Ukraine's interior minister Arsen Avakov accused Moscow of occupying Sevastopol airport and an said "armed invasion" of Crimea was under way.

Simferopol, the other main Crimean airport, has also been occupied by militiamen.

Russia was bolstering an ongoing army drill in the western military district, which began after a surprise order by President Vladimir Putin, with 80 more combat helicopters.

A Russian government official recently revealed that Russia would be willing to go to war over Crimea.

The region lies on the northern coast of the Black Sea. Russia's massive Black Sea Fleet is stationed at Sevastopol and 60% of the region's population are ethnic Russians.

The Russian elite views Ukraine as part of the Soviet sphere of influence and sees the country as a potential bulwark against the growth of EU liberalisation.

The US has warned Russia to refrain from any military drill in the region.

"We expect other nations to do the same. And so we are closely watching Russia's military exercises along the Ukrainian border. We urge them not to take any steps that could be misinterpreted or lead to miscalculation during a very delicate time," said the White House.