Caption:Pro-Russia protesters guard a barricade outside a regional police building seized by armed separatists in Slavyansk on April 13, 2014. Ukraine on Sunday launched an 'anti-terrorist operation' in the eastern town of Slavyansk, where pro-Russian gunmen have seized police and security services buildings, Interior Minister Arsen Avakov said. AFP PHOTO / GENYA SAVILOV (Photo credit should read GENYA SAVILOV/AFP/Getty Images)
Caption:Pro-Russia protesters guard a barricade outside a regional police building seized by armed separatists in Slavyansk on April 13, 2014. Ukraine on Sunday launched an 'anti-terrorist operation' in the eastern town of Slavyansk, where pro-Russian gunmen have seized police and security services buildings, Interior Minister Arsen Avakov said. AFP PHOTO / GENYA SAVILOV (Photo credit should read GENYA SAVILOV/AFP/Getty Images)

    JUST WATCHED

    Gunmen seize police station in Ukraine

MUST WATCH

Gunmen seize police station in Ukraine

CNN's Nick Paton Walsh reports on Ukraine's announcement that they are launching an anti-terrorism operation.

Gunmen seize police station in Ukraine

CNN's Nick Paton Walsh reports on Ukraine's announcement that they are launching an anti-terrorism operation.