Ukrainian and Russian soldiers in stand-off at Crimea military base

Tensions remain high in the Crimean peninsula in Ukraine as European observers were again blocked from entering the by armed men.

There was a stand-off between Ukrainian soldiers and troops, thought to be Russian, at a military base outside Sevastopol.

Two trucks of Russian-speaking armed men arrived and quickly surrounded the base.

The Ukranian commander told ITV News' Senior International Correspondent John Irvine: "They have come to protect us. So why are their guns pointing towards our base?"

The base commander was unable to contact his superiors as radio contact was blocked by a Russian signal jammer.

As John reports from inside the base, Putin's claims that these soldiers, professional in their weaponry and demeanour, are not Russian "are farcical":

John tweeted updates on the situation as it unfolded on the base: