Unarmed Ukrainian troops march to Belbek base
Unarmed Ukrainian troops march to Belbek baseReuters

A particularly dramatic confrontation in the stand-off between Russia and Ukraine was caught on film Tuesday, as Russian soldiers in the Belbek Air Base in Ukraine's Crimean peninsula fired in the air. Russia took over the base on Saturday, in an act of aggression that has sparked international tension.

When the 200 Ukrainian soldiers who were formerly stationed at the base marched unarmed towards the site to speak with the Russians on Tuesday, they were met by warnings that they would be shot, and by actual shots fired in the air. The drama can be seen here:

The footage of Russian troops firing shots in the Crimea belies Russian President Vladimir Putin's claims earlier on Tuesday that no Russian troops were in Crimea. At the same time, Putin said regarding Russian military intervention "I want you to understand clearly: if we do this, it will only be to protect local people."

Russia's military posturing was highlighted Tuesday afternoon, when the country conducted a successful test of a nuclear-capable intercontinental ballistic missile near the Caspian Sea. The same day, a new front nearly opened as Turkey scrambled eight F-16 fighter jets to stop a Russian surveillance plane flying along its Black Sea coast.

The various Russian moves of aggression sparked the US to threaten Russia with sanctions on Monday. The American administration also noted it was discussing sending $1 billion in loan guarantees to provide structural support to Ukraine's economy.