Mr Karayev could have been killed by a sniper, reports say
The mayor of the capital of Russia's North Ossetia region has been assassinated by unknown gunmen.
Vitaly Karayev died from gunshot wounds in hospital after he was attacked in Vladikavkaz on Wednesday morning.
Police have sealed off the area and say that a murder investigation is now under way.
The southern Russian region, like neighbouring Ingushetia and Chechnya, has suffered sporadic violence from militant groups in recent months.
Mr Karayev, aged 46, was shot at about 0900 local time (0600 GMT), as he was leaving his home in a car, officials say.
He suffered several bullet wounds and later died in Vladikavkaz's hospital.
Some reports in the Russian media say the mayor could have been killed by a sniper.
North Ossetian President Taimuraz Mamsurov said he would hold urgent talks with regional security officials to discuss the situation, the Interfax news agency reported.
Meanwhile, Russian President Dmitry Medvedev urged investigators to take "all possible measures" to find the perpetrators, a Kremlin spokesman told the Ria Novosti news agency.
Earlier this month, 12 people were killed in what officials believe was an attack by a female suicide bomber in Vladikavkaz.
North Ossetia was the scene of the Beslan school siege in 2004, in which pro-Chechen militants seized schoolchildren and teachers, and wired up bombs in the school. It ended with the deaths of more than 300 people when explosions erupted and Russian troops stormed the school.
North Ossetia has tense relations with neighbouring Ingushetia, that stem from an outbreak of sectarian violence in the 1990s.
Ingushetia itself suffers almost daily shoot-outs and explosions.
The Georgian breakaway region of South Ossetia - scene of a brief war between Russia and Georgia in August - also borders on North Ossetia. Thousands of Russian troops remain in South Ossetia.