* Acting head of Khasavyurt region shot dead
* Two men killed in separate incident in Dagestan
(Adds Moscow killing)
MOSCOW, Sept 27 Gunmen killed a senior official from Dagestan in Moscow on Sunday, news agencies reported, the first in a recent series of violent attacks linked to the volatile North Caucasus region to reach the Russian capital.
Unidentified gunmen shot dead the acting head of the Khasavyurt region of Dagestan, Alim-Sultan Alkhamatov, an official who had earlier survived three separate attempts on his life, Interfax news agency cited a police source as saying.
The attack with a Kalashnikov automatic rifle, which took place in southwest Moscow and also seriously wounded Alkhamatov's driver, followed the murder of another senior official in Dagestan itself on Sunday.
Growing turbulence in the north Caucasus has become a major headache for the Kremlin. Fears among officials and analysts have grown in recent weeks that the violence could spill over into other parts of Russia, including Moscow.
Moscow police said that a double murder had taken place in the south of the city, but declined to give further details. Prosecutors and investigators could not be reached for comment.
Earlier on Sunday, Alim-Sultan Atuyev, the deputy chief of criminal investigations in Dagestan's interior ministry, was gunned down in a village along with a policeman, who was a relative.
"(They) were shot dead by three men outside a house... The gunmen have escaped," Interfax quoted Dagestan's interior ministry spokesman as saying.
The spokesman added that Atuyev's position was being treated as a "likely cause of his murder".
A rise in suicide bombs and armed attacks on police and security forces in Chechnya, where Russia has fought two separatist wars, and in the neighbouring, mainly Muslim regions of Ingushetia and Dagestan, has shattered a few years of relative calm in the North Caucasus.
Local leaders have warned Russian President Dmitry Medvedev that an Islamist uprising has permeated all spheres of society in the region and that they are struggling to combat it. (Reporting by Robin Paxton and Amie Ferris-Rotman; Editing by Michael Roddy)