By Laurence Peter
International aid is being rushed to Georgia to deal with a humanitarian emergency created by the country's conflict with Russia.
Panic gripped civilians in Gori when Russian planes struck
The UN refugee agency, UNHCR, says nearly 100,000 people have been uprooted by the conflict over South Ossetia.
Georgia was already struggling to help some 275,000 people displaced in the early 1990s by fighting in South Ossetia and another breakaway region, Abkhazia.
The UNHCR says about 56,000 people fled Gori, a key town just outside South Ossetia, after Russian air raids. That amounts to about 80% of the town's population.
Georgia says dozens of civilians were killed when Russian bombs hit two blocks of flats in Gori. Reporters saw casualties at the scene, but the death toll has not been independently confirmed.
Tskhinvali in ruins
Reports from the UNHCR and Russian media speak of total devastation in the South Ossetian capital Tskhinvali, with few buildings left intact after intense bombardments and street fighting.
War casualties have been treated in a hospital basement in Tskhinvali
Russian television showed pictures of a heavily damaged hospital in Tskhinvali, with wounded civilians lying in makeshift wards in the basement.
Families huddled in cellars, trapped by the fighting. They said they had had very little food and water for several days.
The intense fighting cut off supplies of running water and electricity. In many cases separated families were unable to contact each other by phone. Thousands did manage to flee - but often with few possessions.
Russian officials say more than 1,500 civilians were killed in Tskhinvali after Georgia launched an all-out assault last Friday, using heavy artillery and tanks. The casualty toll cannot be independently verified.
Giorgi Gogia, a researcher for Human Rights Watch in Tbilisi, described the Russian figure for Tskhinvali as "an exaggeration", adding: "It is clear that both sides are exaggerating, and that figures are inflated".
He said HRW, which is based in New York, had not found any evidence to back up Russian claims of atrocities committed by Georgian troops.
More than 30,000 civilians fled the fighting in Tskhinvali, Russian officials say. Most of them went to North Ossetia, which is part of the Russian Federation.
Several thousand fled south into Georgia and up to 12,000 people are estimated to be displaced within South Ossetia, officials say.
On Tuesday Russian television said an 80-vehicle Russian convoy carrying relief supplies - water, water filters, food and medicines - had got into Tskhinvali, despite continuing skirmishes on the town's outskirts.
It was the second such convoy to get into the ruined town. At least two field hospitals have also been set up.
Further south, a UNHCR-chartered Boeing 707 cargo plane landed at Tbilisi airport on Tuesday, carrying 34 tons of tents, jerry cans, blankets and kitchen sets.
The damage to Tskhinvali's infrastructure appears to be colossal
The International Committee of the Red Cross (ICRC) is negotiating with the Russian authorities to gain access to South Ossetia.
Yuri Shafarenko, an ICRC spokesman in North Ossetia, said ICRC workers were busy distributing aid to South Ossetians who had fled north.
Thousands of South Ossetians are registering with the Russian migration service, he told the BBC News website on Tuesday.
"Today we delivered emergency relief such as bed linen, blankets, to about 600 refugees from South Ossetia... we have also delivered five medical tents for treating war-related wounds," he said.
ICRC emergency supplies have been sent to Russian hospitals in Vladikavkaz, Beslan, Alaguir and Ardon. Local sanatoriums and summer camps are among the facilities that have taken in South Ossetians.
Another major task for relief workers is to reunite families separated by the fighting.
The ICRC has launched a preliminary appeal for $7.4m (£3.9m) to help meet the emergency needs of displaced people in Georgia. That should help cover the costs of an ICRC surgical team that is going to help Georgian medics.
It is not yet clear how many prisoners-of-war are being held on both sides. The ICRC has visited two wounded Russian pilots held in Georgia and is trying to visit all the POWs.