TBILISI, March 12 (Reuters) - Georgia said on Monday three Russian helicopters had attacked a disputed gorge under Georgian control in the breakaway region of Abkhazia, an incident likely to worsen tensions between Moscow and Tbilisi. Russia's air force denied the reports. Moscow-backed separatists rule most of Abkhazia, which broke away from Georgia in a war in the 1990s, but their government is not recognised internationally. The Kodori gorge has long been a flashpoint for tension. Its upper part is occupied by Georgian security forces and a local pro-Georgian administration while the lower part is controlled by Abkhazian separatists. Russian helicopters late on Sunday fired on the upper Kodori gorge, the de facto border between Abkhazia and Georgia, Shota Khizanishvili, chief-of-staff at the Georgian interior ministry, told Reuters. "Three helicopters bombed the gorge for a half an hour. They were Russian helicopters. There are no victims, but several buildings were partly destroyed," Khizanishvili said. Russia's air force called the Georgian announcement a "provocative act", RIA news agency reported. A source in the pro-Tbilisi administration in the gorge said two villages were also attacked with rockets from Abkhazia. "These two actions took place at the same time. We are dealing with a co-ordinated action from Russia and the Abkhazian separatists -- there is no other way to explain how these actions happened simultaneously," the source said. Abkhazian separatist officials said they had no information about the incident. Georgia's army and air force were put on alert after the raid, Deputy Defence Minister Levan Nikoleishvili said. A Georgian helicopter crashed, killing the servicemen, after being scrambled, he said. Georgian President Mikhail Saakashvili plans to return early from Kazakhstan, where he made a stopover after an official visit to Japan, his press service said. Relations between Tbilisi and former Soviet master Moscow have been severely strained by a spying row, trade disputes and the ambitions of Georgian leaders to join NATO and the European Union.
