The African Union mission, charged with monitoring Sudan's Darfur region, shoulders the enormous burden of providing security to some 2.5 million displaced people spread across a remote area the size of France. The AU has, at most, about 7,000 troops in the region. When the AU mission comes under attack, it is the displaced that suffer most.

Sudanese refugee woman hold a sign saying no to rape (File photo)

As the conflict rages on, the AU's most vocal critics are often the IDP's, themselves, who say the AU simply cannot protect them.

On February 1, an unarmed African Union civilian police officer was shot dead and his vehicle stolen while on a routine patrol at Kassab IDP camp - home to 30,000 people.

The AU immediately ceased patrols to the camp, fearing for the lives of other unarmed officers.

Three weeks later, with the AU still unwilling to patrol, two Darfuri girls, ages eight and 10, were collecting firewood when they were abducted by three armed men who took them to an abandoned hut, made them remove their clothes and raped them.

When the AU resumed patrols, in early March, community leaders gathered to denounce the force for its absence.

"[For] more than four years, they have been repeating the issue of security but the situation is going from bad to worse," said Sheikh Tayyib Adam Nureldin.  "Nothing has been improved. The absence of security is going to create more problems."

AU Civilian Police Chief Ahmed El-Sarafy sought to calm angry community leaders, but he did not apologize for the AU pullout.

El-Sarafy tells VOA the AU had no other choice but to cease patrols, after the murder of the civilian police officer.

"This man was shot for no reason at all. They could have just taken the vehicle and gone. I think there was a message behind this. They don't want us anymore. Killing someone for no reason has to mean something," he said.

After the officer was shot, rebels from the Sudan Liberation Army, who have not signed the Darfur Peace Agreement, claimed responsibility for the incident and offered to hand the killer over to the African Union and return the stolen vehicle.

But the rebels later changed their story, claiming that they had found the vehicle with the keys in the ignition.

They returned the car, but refused to turn anyone over.

Those who suffered most in the wake of the incident were women and girls who no longer had the security provided by AU patrols.

Women are often targeted by men they call Janjaweed members of Arab militia, widely believed to have been armed and supported by the Sudanese government, which used them as a force to crush a 2003 rebellion by African farmers.

Female officers from the AU civilian police interviewed the two rape victims, ages eight and 10 years old.

The younger girl covered her face with her scarf, as she spoke, and would only look at the ground.

She says she and her companion were raped by three men.

The 10-year-old girl said the men warned her not to tell her mother.

Her mother spoke to VOA about the incident.

She says she did not see the men but that her daughter told her they wore the uniforms of soldiers.

Village leader Sheikh Mohamed Abdallah Juma told VOA that, if the men are caught, they should be hanged.

But for now, it seems justice for the young victims may be a long way off.

Only a tiny fraction of rape cases in Darfur have ever reached trial.

The African Union, back on patrol, continues to struggle to do its job in the face of increasing threats.

Wednesday, the African Union reported that two AU peacekeepers were shot dead by former rebels of the Sudan Liberation Army, led by Minni Minnawi.

Minnawi signed a peace agreement with the government of Sudan in May.