Ukraine crisis: Sloviansk is 'fortress' as militants guard roads

Ukraine has declared it will launch a "full-scale anti-terrorist operation" in the east of the country.

It follows further incidents in which pro-Russian militants seized control of key government buildings in eastern Ukraine, despite condemnation from the West.

Attacks in the past 48 hours have happened in Sloviansk, Mariupol and Kramatorsk.

Daniel Sandford visited Sloviansk, which he described as a "fortress" which was "completely in the hands of people loyal to Russia".