The UN human rights council has given unanimous backing to a fresh, independent investigation into mass killings reported in the Sudanese city of el-Fasher.


Our wake-up calls were not heeded. Bloodstains on the ground in el-Fasher have been photographed from space. The stain on the record of the international community is less visible, but no less damaging, UN human rights chief Volker Türk said at an emergency meeting in Geneva on Friday.


Since the civil war began over two years ago, more than 150,000 people have been killed and about 12 million have been forced from their homes.


The new investigation is mandated to identify those who ordered and carried out the massacre in el-Fasher.


The findings could be shared with the International Criminal Court.


While Türk did warn individuals and companies fuelling and profiting from Sudan's war, there is disappointment that the mandate makes no mention of other countries sponsoring the conflict.


The UAE is accused of shipping weapons to the Rapid Support Forces (RSF) paramilitary group, while Iran has been accused of supplying some weapons to the Sudanese army.


Plus, there is concern that the cash-strapped United Nations, already finding it hard to sustain its humanitarian work in Sudan, may not have the funds to mount a really credible inquiry.


El-Fasher was captured last month by the RSF following an 18-month siege. It was the last city in Darfur held by the army and its allies.


The RSF has been accused of targeting non-Arab groups in the city and elsewhere in Darfur - a claim it has denied.


One gruesome feature of this conflict has been the huge volume of footage and photos of horrific atrocities - often seemingly filmed by the culprits themselves, and circulated online. Researchers say this digital evidence will be analysed in a bid to bring the perpetrators to justice.


The people of Sudan, particularly now in el-Fasher, are facing a situation that I never saw before, says Mona Rishmawi, a member of the UN's fact-finding mission on Sudan who has seen the change firsthand over more than two decades.


The scale of the suffering today in Darfur is greater than the Janjaweed militia's genocide in the same region 20 years ago, she told the BBC's Newsday programme. The RSF traces its origins back to the Janjaweed.


Back then, Ms Rishmawi explained, attacks were mainly on villages but now paramilitaries are targeting whole cities and refugee camps housing hundreds of thousands of people.


[There have been] devastating mass killings, rape and torture, disappearances, missing people - and this comes against the background of 18 months of siege and starvation, she said.


A joint G7 statement earlier this week condemned surging violence in Sudan, saying the conflict between the army and the RSF had triggered the world's largest humanitarian crisis.