Prosecutors from Russia and South Ossetia said they were investigating claims of what they called Georgian â€œgenocideâ€ in the separatist region.
Russian investigators say they have identified the bodies of 60 civilians. Initially Moscow said some 2,000 people had been killed by the Georgian army.
A spokesman for the investigative committee said one eyewitness had told him that immediately after the start of hostilities his father was killed, run over by a Georgian tank. His house was also destroyed by mortar attacks.
Apparently all the civilian victims reported so far in South Ossetia had Russian passports, as does the majority of the population. Georgia argues Moscow handed out the passports as a pretext to annex the territory.
Three days of heavy fighting has taken its toll on the South Ossetian capital, Tskhinvali. Those who have dared return to what was left of their neighbourhoods have been shocked by the scenes of devastation.
One woman said: â€œWhat did we poor people do? We have done nothing against them. One crazy man came, another crazy man came and started killing us. The Georgians were killing us and destroyed my house.â€
The Russian authorities have delivered food and other supplies and the Red Cross has also been given permission to organise aid. Tens of thousands of people were forced to flee their homes.