It was early afternoon when the mob surged down an alley of neat rose bushes and halted outside Zarifa's house. The Kyrgyz men broke into her courtyard and sat Zarifa down next to a cherry tree. They asked her a couple of questions. After confirming she was an ethnic Uzbek, they stripped her, raped her and cut off her fingers. After that they killed her and her small son, throwing their bodies into the street. They then moved on to the next house.

"They were like beasts," Zarifa's neighbour, Bakhtir Irgayshon, said today, pointing to the gutted bedframe where she had been assaulted. A few pots and pans remained; the rest of the family home was a charred ruin. Zarifa's husband, Ilham, was missing, Irgayshon said, probably dead. Only his mother, Adina, survived the Kyrgyz-instigated conflagration that engulfed the neighbourhood of Cheremushki last Friday.

The scale of the ethnic killing that took place in Osh – as well as in other towns and villages in southern Kyrgyzstan – was grimly obvious. In the next street were the remains of another victim. He burned to death in his bed. Not much was left, only a jigsaw-like spine and hip. Nearby, Uzbek survivors were retrieving the bodies of seven small children. They had been incinerated, together with their mother, while cowering in a dark cellar.

Witnesses said the attacks by the Kyrgyz population on the Uzbek minority were attempted genocide.

The violence erupted in Osh last Thursday evening, possibly ignited by a row in a casino. But much of it appeared co-ordinated and planned, Uzbeks said. The attacks took the prosperous outlying Uzbek areas of town unawares.

"It started on Friday lunchtime," said Rustam, an Uzbek lawyer. "It came in three distinct waves. The Kyrgyz entered Cheremushki district driving an armoured personnel carrier. This paved the way. Several of them were wearing army uniforms. At first we felt relieved. Someone had come to rescue us, we thought! Then the BKR opened fire and started shooting people randomly.

"Behind them was the second wave. This was a mob of about 300 Kyrgyz youths armed with automatic weapons. Most were very young – between 15 and 20 years old. The third wave was made up of looters and included women and young boys. They stole everything of value, piling it into cars. Then they set our houses on fire."

According to Rustam the official toll from the riots – 178 dead and 1,800 injured – is a woeful underestimate. In reality, around 2,000 Uzbeks were slaughtered, he said, as the pogroms quickly spread from Osh to Jalal-Abad, 25 miles away, and other Uzbek villages in the south. Rustam said: "I carried 27 bodies myself. They were just bones. We are talking here about genocide."

With the violence largely now spent, and only the occasional gunshot disturbing Osh's evening curfew, survivors debated who was to blame. Some suggested Kyrgyzstan's ousted president, Kurmanbek Bakiyev, was behind them – describing the violence as a premeditated attempt by him to take revenge on the new leadership. Bakiyev fled the country in April after bloody protests in the capital, Bishkek. His supporters remain in control in much of the south. They dominate Osh's monoethnic Kyrgyz police and power structures, and also control the local mayor's office.

Few believe the riots could have taken place without the local administration's connivance. But it is clear that other grievances are at play. Ethnic Uzbeks make up 15% of Kyrgyzstan's 5.6 million population, and dominate the towns of Osh and Jalal-Abad. These settlements near the Fergana valley ended up in Kyrgyzstan by accident – when Lenin dumped them there in 1924.

"We're hardworking people. We were never nomadic like the Kyrgyz. We never lived in yurts. For the past 2,000 years we've built stone houses," Rustam said. He acknowledged that the town's Uzbeks were usually better off than their Kyrgyz neighbours. "Since the Silk Road, we've been involved in commerce and trade. We are successful. The Kyrgyz are jealous and resent this."

In the centre of Osh, Uzbek enterprises were in ruins. Shops marked with "KG" for Kyrgyz had been spared. Oktam Ismailova managed to save her home from the flames by sloshing water on her roof. A brick thrown through the window hit her father on the head. He survived. "We can't believe what happened. We are in shock," she said.

When the trouble started, thousands of Uzbeks fled to the Uzbekistan border, just three miles from Osh. Not everyone made it: one witness described how two Uzbek youths drove into a Kyrgyz mob in the centre of town. "They pulled the two Uzbek boys out of the car, and killed them in less than five minutes using sticks and knives. Then they dumped them in the Ak-Bura river," said Maya Tashbolotova, who watched, peering over the fence of her guesthouse.

So far, tens of thousands of refugees have crossed into Uzbekistan. According to Unicef, 90% of them are women, children and the elderly. Today, Uzbek guards sealed the border, a 5ft barbed wire fence. Nearby, Uzbek refugee children were washing in a stream while an old lady beaten in the face was being treated. The mood was one of anger, disbelief and betrayal. Many of the girls arriving at the border had been raped, witnesses said.

"Why did I train to be a surgeon? Was it for this?" said a 35-year-old Uzbek doctor, who declined to be named, crying quietly in the corner of his temporary surgery. The doctor said that many victims had been shot in the face and head. A nurse showed footage on a mobile phone of an Uzbek man who had been doused in kerosene and set alight. His head and arms were blackened stumps. He had no eyes. But he lived for several days, dying two days ago in agony.

"We have been discriminated against for 20 years," the doctor said, referring to the ethnic riots that took place near Osh in 1990, just after the breakup of the Soviet Union. Recently, he said, Kyrgyz chauvinism had grown, fuelled by the weakness of the government, and by a fear that the Uzbek minority was becoming too strong and was prone to secessionist-minded leaders.

There was not much sign of humanitarian relief today, with Kyrgyz drivers too scared to enter Uzbek neighbourhoods. Uzbeks had demarcated their territory by felling maple trees and building makeshift barricades with burned-out cars. Nearby, Kyrgyz soldiers had set up checkpoints in a post-facto show of strength. Some Kyrgyz locals blamed the riots on Uzbek youths, who they said ransacked a local casino.

Back in Cheremushki, Rustam said the events of the last week heralded a return to barbarism in an age seemingly governed by international rules and institutions. Asked who was to blame, he said: "It was the state against us. It was the whole system. It was everything."