Fierce fighting between the forces of rival generals has shaken the Sudanese capital, Khartoum, as disease and malnutrition threaten the rising number of the displaced.
On Sunday, a Khartoum resident said he was shaken from sleep by "violent fighting in which various weapons were used." Another said he was awakened by warplanes.
Battles since mid-April between forces loyal to army chief Abdel Fattah al-Burhan and the paramilitary Rapid Support Forces (RSF) have killed nearly 3,000 people.
Another 2.2 million have been forced from their homes inside the country while almost 645,0 00 have fled across borders for safety, according to the International Organization for Migration.
"The situation is grave," the medical charity Doctors Without Borders (MSF) said in a statement, detailing the hardships of displaced Sudanese stuck in nine camps in White Nile State, which borders South Sudan.
Civilians targeted
In addition to the capital, the worst fighting has been in the western region of Darfur where residents, as well as the United Nations, United States and others, say civilians have been targeted and killed for their ethnicity by the RSF.
The death toll is believed to be much higher than recorded, as the World Health Organization says about two-thirds of health facilities are "out of service" in combat-affected areas.
Many injured are unable to reach hospitals and bodies lie rotting in the streets of Khartoum and Darfur.
A record 25 million people in Sudan need humanitarian aid and protection, according to the UN.
"Hundreds of thousands of people, most of them women and children” pack those camps that stretch out from the south of Khartoum all the way to the border with South Sudan, MSF said.
“There are suspected cases of measles. Malnutrition among children has become a vital health emergency. From June 6 to 7 we treated 223 children with suspected measles, 72 were hospitalised and 13 have died," MSF said.
Extensive damage
The war has smashed the country's already fragile infrastructure, leaving residents short of water and electricity in the oppressive heat.
Numerous ceasefires, including some negotiated by the United States and Saudi Arabia, have failed to hold.
Fighting continued during the just-ended Eid al-Adha holiday for which the warring sides announced separate unilateral truces.
A UN official has warned of possible "crimes against humanity" from the current fighting in Darfur.
Dozens of women have been sexually abused in Darfur and elsewhere, a government unit monitoring such offences has said.
In early June, Darfur governor and ex-rebel leader Mini Minawi, who is now close to the army, declared Darfur a "disaster zone".
Aid organisations are repeating their appeals to the warring sides to open up secure corridors to allow them to reach the injured and those displaced by the fighting.
