Islamic State claims responsibility for murder of Russian intelligence officer

DERBENT , Russia, Dec. 31 (UPI) -- The Islamic State claimed responsibility for the murder of a Russian intelligence officer at a World Heritage Site in the southern Russian republic of Dagestan.

Gunmen opened fire Tuesday on a group of about 20 tourists at the Derbent citadel, a UNESCO World Heritage Site. The victim who died and one of the injured were officers of Russia's intelligence service, the Russian Federal Security Service, a law enforcement official confirmed.

Four of the injured are hospitalized in critical condition, a Dagestan Health Ministry spokesperson said. IS claimed on social media Thursday it initiated the attack, saying it targeted the intelligence officers.

Dagestan is a largely Muslim area of southern Russia, where an Islamist insurgency is in progress. The Islamic State has been established in the republic since June; It claimed responsibility for an attack on an army base in Dagestan in September. The al-Nusra Front, a Syrian group linked to al-Qaeda, has called for organized attacks in Russia in retaliation for Russia's involvement in Syria's civil war.