Black smoke rises over Khartoum in this image from AFPTV video on April 28, 2023
Black smoke rises over Khartoum in this image from AFPTV video on April 28, 2023 AFP

Fierce fighting broke out again Monday between the army and paramilitaries despite the formal extension of a truce, after the United Nations warned the humanitarian situation reached "breaking point".

More than 500 people have been killed since battles erupted on April 15 between Sudan's de facto leader Abdel Fattah al-Burhan, who leads the regular army, and his ex-deputy Mohamed Hamdan Daglo, who commands the powerful paramilitary Rapid Support Forces.

Millions of Sudanese around the capital have since hidden in their homes with dwindling food, water, and electricity as warplanes on bombing raids have drawn heavy fire from anti-aircraft guns.

"Warplanes are flying over southern Khartoum and anti-aircraft guns are firing at it," said one resident, while another witness told AFP he was also hearing "loud gunfire" in the area.

Burhan and Daglo have agreed multiple, poorly observed ceasefires, and extended the latest formal truce on Sunday by 72 hours, with each side repeatedly blaming the other for the frequent violations.

Millions of Sudanese are trapped in the country, where aid workers are among the dead, humanitarian facilities have been looted, and foreign aid groups have been forced to essentially halt all aid operations.

Top UN humanitarian official Martin Griffiths said Sunday he was heading to the region to help "bring immediate relief to the millions of people whose lives have turned upside down overnight".

"The humanitarian situation is reaching breaking point," he said. "Goods essential for people's survival are becoming scarce in the hardest-hit urban centres, especially Khartoum."

"The cost of transportation out of worst-hit areas has risen exponentially, leaving the most vulnerable unable to locate to safer areas."

Some 50,000 people have fled the raging conflict, seeking refuge in neighbouring countries including Chad, Egypt, and the Central African Republic, said the UN refugee agency.

The fighting has also triggered a mass exodus of foreigners and international staff, with countries the world over launching frantic evacuations by land, sea, and air.

Daglo's RSF is descended from the Janjaweed unleashed by former strongman Omar al-Bashir in Sudan's Darfur region, leading to war crimes charges against Bashir and others.

Further complicating the battlefield, Central Reserve Police were being deployed across Khartoum to "protect citizens' properties" from looting, the Sudanese police said, confirming an army statement.

The RSF had warned police against joining the fight.

The US Treasury Department last year sanctioned the Central Reserve for "serious human rights abuses" related to its use of "excessive force" against pro-democracy protests after the October 2021 coup that brought Burhan and Daglo to power.

At least 528 people have been killed and almost 4,600 people wounded in the violence, according to Sudan's health ministry, but the death toll is feared to be far higher.

Fighting has also spread across Sudan, especially in the long-troubled Darfur region, where witnesses reported intense conflict and looting.

At least 96 people were reported killed in El Geneina, West Darfur, the UN said.

The UN World Food Programme has warned the unrest could plunge millions more into hunger in a country where 15 million people already needed aid to stave off famine.

Only 16 percent of health facilities are functioning in Khartoum, according to the World Health Organisation, with many facilities shelled.

On Sunday, a first Red Cross plane brought eight tonnes of humanitarian aid from Jordan to Port Sudan, which is so far untouched by the fighting and has served as an evacuation hub.

The aid included surgical material and medical kits to stabilise 1,500 patients.

Regional powers have joined negotiations to help end the violence.

An envoy of Burhan's met on Sunday in Riyadh with the Saudi Arabian Foreign Minister Prince Faisal bin Farhan, who called for the restoration of calm in Sudan, his ministry said.

Egypt has called an Arab League meeting of its permanent delegates Monday to discuss the "situation in Sudan".

People walk on a deserted street in Khartoum on April 30, 2023, as clashes continue in war-torn Sudan
People walk on a deserted street in Khartoum on April 30, 2023, as clashes continue in war-torn Sudan AFP
Smoke billows over residential buildings in Khartoum on April 30, 2023 as deadly clashes between rival generals' forces have entered their third week
Smoke billows over residential buildings in Khartoum on April 30, 2023 as deadly clashes between rival generals' forces have entered their third week AFP
Sudanese refugees from the Tandelti area shelter in Koufroun, Chad, on April 30, 2023
Sudanese refugees from the Tandelti area shelter in Koufroun, Chad, on April 30, 2023 AFP
Protesters outside the White House, calling on Washington to intervene to stop the fighting in Sudan, on April 29, 2023
Protesters outside the White House, calling on Washington to intervene to stop the fighting in Sudan, on April 29, 2023 AFP
Map of Sudan and neighbouring countries as civilians flee the country during a fragile ceasefire
Map of Sudan and neighbouring countries as civilians flee the country during a fragile ceasefire AFP
US military officers assist US nationals in boarding an evacuation vessel in Port Sudan amid ongoing deadly clashes between army forces and paramilitaries
US military officers assist US nationals in boarding an evacuation vessel in Port Sudan amid ongoing deadly clashes between army forces and paramilitaries AFP
Fighters of the paramilitary Rapid Support Forces seen in an image from footage they released on April 23, 2023
Fighters of the paramilitary Rapid Support Forces seen in an image from footage they released on April 23, 2023 AFP