The BBC's Fergal Keane witnesses an assault by Sudan's security forces on a refugee camp in the troubled region of Darfur.
The first police action at El-Geer refugee camp near Nyala began soon after midnight.
Samira temporarily lost her baby during the assault
I saw at least four jeep-loads of police driving over the flimsy shacks erected by displaced people.
Later they returned and began to beat and tear-gas the frightened crowd.
I saw one of the community leaders being thrown to the ground and attacked by several policemen.
The police launched tear-gas grenades into a compound where women and children were sheltering.
Police then entered and forced them to flee.
A police commander at the scene told me he was under orders to move the people to a new camp several kilometres away.
Forcible relocation is a grave breach of international humanitarian law, but the international community is powerless here.
The police showed open contempt for United Nations officials when they arrived, firing tear-gas grenades and driving aggressively around the camp.
African Union (AU) peacekeepers at the camp said they did not have power or mandate to intervene.
More police have now arrived to reinforce the earlier contingent.
The UN representatives pulled out of the camp for security reasons.
All of this took place on a day when the UN representative in Sudan, Mr Jan Pronk, was due to visit the camp to talk with local officials. Government officials in this area knew this.
For the UN and African Union, this assault on El-Geer camp is a calculated affront.
The police staged two assaults on displaced people, and wouldn't desist from bulldozing their camp, despite the presence of representatives of the UN, AU and international aid agencies.
Some 1.6m people have fled their homes in the conflict
At one stage a plastic bullet was fired at a BBC cameraman standing next to a UN vehicle.
The BBC has also confirmed that tear gas was fired at people, mostly women and children, queuing at a nearby medical clinic.
We witnessed harrowing scenes.
One woman was crying hysterically because her baby son had been lost in the panic. She later found him.
A number of men and women were also arrested.
The displaced people here are vulnerable and defenceless, and they felt real terror.
All the people here I have spoken to were driven out of their own villages by the pro-government Janjaweed militia and have witnessed rape and murder.
It is really hard to convey what it is like, when in the dark hours of the early morning, jeeps come in with searchlights, knowing that these people have absolutely no protection.
I've been covering Africa for 21 years and I thought I'd seen everything, but to watch the officials and the police of a state like Sudan - which has just signed a peace agreement - demolishing people's shacks under the eyes of international observer and breaching international law, is quite extraordinary and unique.
The population is terrorised and bewildered, with little faith in the power of the international community.