Ukraine crisis: Casualties in Sloviansk gun battles

A Ukrainian officer has been killed in a gun battle with pro-Russian armed men in the eastern city of Sloviansk, the interior minister has said.

Both sides suffered a number of casualties, Arsen Avakov has stated.

Pro-Russian forces took over Sloviansk on Saturday and have targeted at least four other cities, prompting Kiev to launch an "anti-terror operation".

David Stern reports from Donetsk.