South Ossetia's capital Tskhinvali was devastated by shelling
Both Russia and Georgia violated the laws of war when they clashed in South Ossetia last August, failing to protect civilians, Human Rights Watch says.
The New York-based international rights organisation has produced a report on the conflict, based on more than 460 interviews done in the region.
The group accuses Georgia of attacking South Ossetia "with blatant disregard for the safety of civilians".
"Indiscriminate" Russian air and ground attacks killed many civilians, it says.
Call for justice
Russia allowed South Ossetian forces to kill, beat, rape and threaten civilians, Human Rights Watch (HRW) says, demanding that those responsible be brought to justice, and their victims compensated.
During the conflict in and around the breakaway region in Georgia, all parties insisted they had done everything possible to minimise civilian casualties.
Georgia's attempts to regain control of South Ossetia were repelled by Russian forces.
Rachel Denber, HRW's Europe and Central Asia director, said much of the argument after the conflict had focused on who was to blame for starting it.
But that "misses the point, which is the urgent need to hold all who are responsible accountable and to allow displaced people to return home safely," she said.
Human Rights Watch condemned Georgia's use of Grad multiple rocket launchers in civilian areas. The rockets "cannot be targeted with sufficient precision to distinguish between civilian and military objects," the group said.
Russian forces have mostly pulled back to their former positions
It said both Russia and Georgia used cluster munitions, "causing civilian deaths and putting more civilians at risk by leaving behind unstable 'minefields' of unexploded bomblets".
"Instead of protecting civilians, Russian forces allowed South Ossetian forces who followed in their path to engage in wanton and widescale pillage and burning of Georgian homes and to kill, beat, rape, and threaten civilians," said Ms Denber. "Such deliberate attacks are war crimes."
More than 20,000 ethnic Georgians who fled the conflict remain displaced, HRW says.