Violence has spiraled across Georgia's breakaway region of South Ossetia, prompting deep concerns over the fate of the province's 75,000 residents.
Georgian forces overnight began pounding the South Ossetian capital, Tskhinvali, in a large-scale operation to regain control of the Moscow-backed separatist region. Both sides accuse each other of initiating the hostilities.
The offensive -- which followed days of renewed clashes -- sparked a furious reaction from Russia, which sent troops, military aircraft, and tanks to repel Georgian forces.
Vladimir Pletnyov, a Russian television journalist who traveled to the South Ossetian capital of Tskhinvali late on August 7, told RFE/RL's Russian Service that South Ossetian civilians were fleeing en masse.
"Huge numbers of South Ossetia residents are leaving for Russian territory," he said. "In principle those who want to leave, leave -- and those who don't stay and pray that nothing terrible happens to them."
The fighting is the worst violence in the region since South Ossetia and Abkhazia broke away from the central Georgian government in a war in the early 1990s.
Civilian Casualties Feared
Death tolls have been raising on all sides throughout the day; South Ossetia's rebel leader Eduard Kokoity claimed hundreds of civilians have already been killed in Tskhinvali.
(Reuters video: Russian military vehicles in the pre-dawn hours head toward the border of South Ossetia where they crossed into the breakway republic. Georgian forces launch a series of attacks on separatist positions there. Russian peacekeepers take cover as Georgian jets fly overhead.)
Television stations around the world broadcast footage of panic-stricken South Ossetians fleeing the bloodshed after Georgia imposed a three-hour humanitarian cease-fire. According to the commander of the Russian peacekeeping force in the region, Tskhinvali is "almost completely destroyed."
The International Committee of the Red Cross warned of a humanitarian crisis, saying local hospitals were overflowing and people were sheltering in their basements with no electricity or access to the outside world. Water is also reportedly in short supply, and shops are running out of food.
Russian Foreign Minister Sergei Lavrov said Moscow was receiving reports that ethnic cleansing was taking place in South Ossetia.
"We see panic rising among the population and the number of refugees trying to save their own lives and the lives of their children and families growing," Lavrov said. "A humanitarian catastrophe is at hand."
Russian soldiers dispatched to Tskhinvali said they have begun firing at Georgian forces, the first confirmed engagement between the two nations' regular troops.
Ties between Moscow and Tbilisi have soured in past years over Moscow's political and financial support for Georgia's two breakaway provinces, where most residents have been handed Russian passports. Georgia, in turn, has angered Moscow by pushing for NATO membership.
The Organization for Security and Cooperation in Europe (OSCE) called on Russians, Georgians, and South Ossetians to "pull back from the brink of a full-fledged war." Top officials in France, Germany, and Turkey have also called for an immediate end to hostilities.
But the violence and angry rhetoric has shown no sign of abating.
Speaking in a televised address, Georgian President Mikheil Saakashvili accused Russia of conducting air strikes on Georgian territory and described Russia's military intervention as "international aggression in its classical sense."
Saakashvili ordered a full-scale mobilization of military reservists. "Everyone should appear at recruiting centers," he said. "We have to save our country together."
President Dmitry Medvedev, in turn, said Russia would "not allow the death of our compatriots to go unpunished." Russian Prime Minister Vladimir Putin, on a visit to Beijing, lambasted the Georgian leadership for what he described as "very aggressive actions" that he said killed several Russian peacekeepers
Russia also announced it will cut all air links with Georgia from midnight on August 8.
Factbox -- South Ossetia
Status: The region broke away from Georgia in a 1991-92 war. A peacekeeping force with 500 peacekeepers each from Russia, Georgia, and North Ossetia monitors a 1992 truce.
Population: Approximately 70,000 (according to the 1989 census, about two-thirds Ossetian, one-third Georgian)
Languages: Ossetian, Georgian, Russian
Religion: Orthodox Christianity
South Ossetia: Timeline Of A Crisis