Adama (Ethiopia) (AFP) - She was not one of them, but Saada Youssef had lived alongside the Somali people of eastern Ethiopia for years. Then came the day local officials told her to leave or die.
"Even on the truck, people were throwing stones at us," Saada said, recalling her escape in a vehicle sent to rescue people of Oromo ethnicity living in the Somali region where tit-for-tat ethnic violence killed hundreds last month.
Saada found refuge in a collection of abandoned buildings in Adama, a city far from her home in the eastern town of Wachale, one of several areas in Ethiopia's Oromia and Somali regions that have seen fighting between two of the country's largest ethnic groups.
The bloody clashes threaten to upset the delicate ethnic balance of Africa's second most populous country, where the all-powerful ruling party last year declared a state of emergency to end months of sometimes deadly anti-government protests spearheaded by the Oromos.
The unrest raises questions about the future of Ethiopia's "ethnic federalism" system of governance, which is supposed to offer a degree of self-determination to the country's diverse peoples but which critics say is often overruled by the federal government.
- A permanent rupture? -
What triggered September's violence is unclear, but its results are not.
A government spokesman said hundreds of people have been killed in recent weeks and a local official in the eastern city of Harar said that more than 67,800 Oromos alone have fled, not to mention the Somalis who have moved in the opposite direction.
Survivors of the ethnic fighting blamed the government for not doing more to stop the bloodshed. They are worried it might lead to a permanent rift between the country's Somali and Oromo communities.
"This could be ethnic cleansing," said Molu Wario, an Oromo who fled fighting in Moyale in the south along the border of the Somali and Oromia regions, after a land dispute turned ugly.
"It has led to hostility, and the relationship between us will never be the same as before," he said.
The logic of ethnic federalism sees different communities running their own affairs, so Somalis are in charge of the Somali region while Oromos run Oromia, but communities mix in all nine of Ethiopia's regions and squabbles over land and resources are common, though not always so violent.
This time, Somali and Oromo leaders alike allege atrocities committed by the other to justify their attacks.
Somalis point to a clash in Awaday, a town in Oromia, where they claim Oromos killed 18 Somali traders who were selling khat, a leafy plant that is a mild stimulant when chewed and is hugely popular in Ethiopia.
They also claim Oromos burned eight children to death in a district along the shared regional border and murdered patients in a hospital.
The claims could not be independently verified, though a diplomat in the capital Addis Ababa said the Oromia region's police force took part in the clashes.
Whatever the truth of the allegations, the retribution they have spurred is real.
- 'I have nothing left' -
Fleeing Oromos say the Somalis who chased them away from their homes with knives and guns cited the attack in Awaday.
Abdel Jabbar Ahmed, who escaped from Wachale, said he was told: "The Oromos killed 20 Somalis in Awaday, so we are going to take all the Oromos inside Somali region out."
Other dispossessed Oromos said their Somali friends and neighbours sheltered them when violence broke out, but that the regional security force -- known as the Liyu police and repeatedly criticised by rights groups -- was responsible for the worst of the excesses.
Ayub Abdullah, an Oromo day labourer who lived for 15 years in the Somali regional capital Jigjiga, said he was confronted by a mob at work, who demanded to know his ethnicity.
Then, four Liyu police attacked him and throttled him with a rope. Afterwards Ayub fled to a camp for displaced Oromos on the outskirts of Harar, a walled city near the border between the two regions.
"I work with lots of different people, but it was only Oromos who were being targeted," he said.
The military now guards major roads along the flashpoint border areas, gradually restoring calm to restive areas such as Jigjiga and Moyale.
But among the displaced, there's little talk of return.
"I saved all I had for 20 years and I lost it at once. Why would I go back there?" Saada said. "I have nothing left there."