MOSCOW, August 8, 2008 (AFP) - Russian troops are on the edge of the capital of the breakaway Georgian region of South Ossetia, Russian news agencies reported on Friday, after Georgia said it had full control of the city.

'Units of the 58th Army have been sent to assist Russian peacekeepers and are on the edge of Tskhinvali,' Igor Konashenkov, an assistant to the commander of Georgia's armed forces, was quoted as saying.

Russia's defence ministry earlier said it had sent reinforcements to its contingent of peacekeepers in South Ossetia in order to protect its citizens in the region.

Most of South Ossetia's 70,000 residents have been granted Russian citizenship since the Soviet collapse of 1991.

'We will not allow the death of our countrymen and peacekeepers to go unpunished. We have sent reinforcements into the region to help our peacekeepers,' the ministry said in a statement.

The statement came shortly after about 50 heavy Russian tanks, trucks and troops were seen by an AFP reporter Friday heading towards South Ossetia, traveling through the Russian province of North Ossetia.

Georgia's National Security Council warned that Moscow and Tbilisi would be in 'a state of war' if the reports of a Russian military convoy entering South Ossetia proved true.

Georgia also reported that Russian military planes had bombed an area near the capital Tbilisi and claimed that it had downed two of the planes. There was no confirmation of that claim on the Russian side.