TBILISI - Russian troops backed by tanks and fighter jets seized control of South Ossetia on Sunday as fears grew of a wider conflict with Georgia over Moscow-backed separatist regions. Georgia said it had withdrawn most of its troops from South Ossetia in the face of a build-up in Russian firepower and that it had lost control of the near-destroyed regional capital, Tskhinvali. It also said had ordered its forces to cease fire in the breakaway region and offered to immediately begin talks with Russia to end hostilities, Georgia's Foreign Ministry said in a statement. Shortly after the statement was issued, however, bombs fell on the outskirts of the Georgian capital Tbilisi targeting a military air force facility located close to the international airport, an AFP reporter witnessed. Russian planes also dropped a bomb 200 metres from the runway at Tbilisi International Airport, Interior Ministry spokesman Shota Utiashvili told AFP. A Russian Foreign Ministry official, quoted by Interfax, contradicted the Georgian statement, saying Georgian forces on the ground were in fact continuing military action. UN observers in Georgia confirmed that a military airport near the Georgian capital Tbilisi was bombed, a top UN official said Sunday. Russia's defence ministry on Sunday denied that Russian forces had dropped a bomb near a runway at Tbilisi International Airport, branding the report "disinformation," Interfax reported. As diplomatic efforts intensified to bring an end to the crisis, officials in Tbilisi said Moscow had begun bombing Georgian territory in and around another restive province, Abkhazia, but this was denied in Moscow. Over 4,000 Georgian troops on Sunday massed near its breakaway region of Abkhazia, the Interfax news agency quoted Abkhaz rebel leader Sergei Bagapsh as saying. Georgian Reintegration Minister Temur Yakobashvili told journalists that Georgia's western city of Zugdidi had been bombed and that Russian battleships had been moved to the nearby Black Sea. Georgia's Interior Ministry said Russian aircraft had also bombed villages in the Kodori Gorge, the only Georgian-controlled area of Abkhazia. Abkhaz separatist leader Sergei Bagapsh said his territory's air force and artillery was conducting an operation to force out Georgian troops from the Kodori Gorge independently of Russia. Russian President Dmitry Medvedev on Sunday termed Georgian military operations in South Ossetia "genocide", as "they were on a mass scale and were directed against individuals", according to Russian news agencies. Abkhazia's leader Sergei Bagapsh on Sunday decreed a 10-day "state of war" in areas close to Georgian-controlled territory, Russia's Interfax news agency reported. Russia's armed forces denied plans to expand their conflict with Georgia into the breakaway region of Abkhazia after Tbilisi said Russia was taking military action there. "We do not plan to escalate the conflict in this region," Russian army spokesman Anatoly Nogovitsyn said in televised remarks, referring to Abkhazia, which like South Ossetia is a Russian-backed separatist region of Georgia. Russia's armed forces denied plans to expand the conflict into Abkhazia, but a resident of Zugdidi told AFP she had heard planes and bombing early Sunday. "We do not plan to escalate the conflict in this region," Russian army spokesman Anatoly Nogovitsyn said in televised remarks. Russian officials said they were in control of Tskhinvali in South Ossetia but added that Georgia still had about 7,400 servicemen, 100 tanks and artillery pieces in the area. Russia puts the death toll from hostilities that broke out last week at 2,000 while Georgia estimates range from 92 to 150. Clashes in and near the Kodori Gorge came amid reports that Russia was boosting its naval presence in Abkhazia. Georgia said it had withdrawn most of its troops from South Ossetia and claimed Moscow had brought in 10,000 extra troops as well as building up a force of armoured vehicles on the Russian side of the border with Georgia. The Secretary of Georgia's National Security Council, Alexander Lomaia, told AFP that Russian navy vessels had arrived in the Abkhaz port of Ochamchire and Georgia's government said in a statement that 4,000 troops had landed at the port. He further said Russian troops are heading in the direction of the Georgian town of Gori, which Georgian forces are positioned to defend. The movement of Russia's naval fleet from their base in Ukraine to positions near Georgia also threatened to destabilise the region. Ukraine's Foreign Ministry threatened to prevent the warships from returning to their base in the Ukrainian port of Sevastopol. A Russian press report claimed the battleships were preparing to implement a sea blockade on Georgia, but this was also denied in Moscow. The flagship of Russia's Black Sea fleet and other naval vessels put in at the Russian port of Novorossiysk on Sunday, Interfax reported, as Moscow sought to dispel claims it was blockading Georgia's coast. Two ships were accompanied by three large landing craft and a protection vessel, the agency said, citing a source in the Novorossiysk administration. Russia's military earlier said the ships had been deployed near Georgia's territorial waters amid a fierce conflict over the separatist Georgian territory of South Ossetia. Georgia's army of less than 25,000 men is confronting a Russian force which can count on more than one million troops and has dominance of both skies and sea. Georgian President Mikheil Saakashvili called on Nato and the United Nations to "stop Russian aggression", in an interview with a German newspaper. "Above all I think they have one moral duty: to speak with a united voice and stop Russian aggression," he told the daily Rhein Zeitung, when asked about the role NATO and the UN should play in Georgia's conflict with Russia.