Crimea: 'Shots fired' at military base in Simferopol
18 March 2014 Last updated at 16:34 GMT
A Ukrainian serviceman has been shot and killed in an attack on a base in Crimea, according to the defence ministry.
The attack reportedly took place shortly after Russian President Vladimir Putin signed a bill to absorb the peninsula into Russia.
The BBC's Ben Brown, reporting from outside the base in the capital, Simferopol, said that bursts of automatic gun fire were heard.