BBC - Sudan's army has been accused of launching several drone strikes that have reportedly killed more than 300 people, including dozens travelling to a funeral.
The death toll from strikes in two areas of West Kordofan state on Sunday evening was 150, sources told the Sudan War Observatory, which tracks the conflict that erupted in 2023 between the army and the paramilitary Rapid Support Forces (RSF).
In Abyei, a disputed border area between Sudan and South Sudan, 153 people were killed when drones hit a market on Monday, the region's information minister said.
A military source told the BBC the army had carried out the Abyei attack, saying the market was a fuel supply site for the RSF.
The attack has raised tensions between South Sudan and Sudan, which jointly administer Abyei, as they both claim ownership to the oil-rich region in a dispute that has remained unresolved since South Sudan ceded in 2011.
South Sudan has summoned Sudan's ambassador to lodge a formal protest. There are fears the conflict could spill across the border.
Despite a partial arms embargo on Sudan, foreign countries have been supplying both the army and the RSF with drones and they are increasingly becoming the weapon of choice in the conflict.
The war has created one of the worst humanitarian crises in the world, killed hundreds of thousands of people and forced more than 14 million from their homes.
"We are alarmed by the continued deadly drone strikes across the country that are killing civilians, including children, and that are disrupting essential services," UN spokesperson Stéphane Dujarric said on Monday.
The rising use of armed drones came as 20 million people faced acute hunger, with a rising risk of famine in parts of the western region of Darfur and Greater Kordofan, he said.
Greater Kordofan comprises three states and is a vital axis linking Darfur, controlled by the RSF, to the capital, Khartoum, now in army hands.
The wave of drone attacks started on Sunday evening and, according to the Sudan War Observatory, it is likely they were launched from the army-held city of Kadugli in South Kordofan state.
A truck carrying around 200 mourners which had travelled from an area north of Abyei was hit as it arrived in the town of Al-Dabab in West Kordofan, the monitoring group said.
Sources told the group that 145 people were killed and a tent where mourners at the funeral had gathered was also hit, killing five others. A further 150 people were injured in the attacks, it said.
Army drones also bombed a market in the town of Al-Mujlad in West Kordofan on the same evening, according to the Sudan War Observatory, which said the exact number of deaths and injuries were not yet known.
Sudan's army has not responded to the allegation it carried out these strikes, but said it did not attack civilians even if they believed there were RSF fighters amongst them.
The attack in Abyei, which borders West Kordofan, took place on Monday around 11:30 local time (09:30 GMT) targeting Amiet Market around 10km (six miles) from Abyei town, the region's Information Minister Yohana Akol Ngor told Radio Tamazuj, which broadcasts from the Netherlands to audiences on the Sudan-South Sudan border.
On Tuesday, the minister confirmed to the Associated Press and Reuters that the death toll had risen from 73 to 153 people.
"It is a horrible and shocking situation," AP quotes him as saying.
BBC Verify has studied satellite images that show extensive burnt buildings in the north-east corner of Amiet Market, which is also known in Arabic as Al-Na'am Market. Older images from the area show it is usually full of trucks.
It has also verified footage filmed near the market that shows a large plume of smoke, at least one petrol tanker and someone talking about five missiles being fired. Another verified video shows two massive, separate fires coming from buildings near that section of the market.
"The market was completely destroyed. The bombing spread terror and fear among the local population," market trader Fadlallah Adam Hamouda told BBC Arabic's Middle East Daily.
Another trader told the BBC the attack had come as shock as UN peacekeepers have been in Abyei since 2011 - with more than 2,800 uniformed personnel currently deployed.
"Our area is a weapons-free zone under United Nations protection, yet it was targeted by drones," he said.
"The attack caused extensive material damage after the fuel market was struck, sparking a massive fire that spread to nearby homes."
Earlier, Ngor told Reuters that emergency workers had struggled to retrieve the bodies because of fires caused by the strikes.
On Monday, medical charity Médecins Sans Frontières (MSF) said it had also received people wounded in the attack at Ameth Bek Hospital in Abyei town.
"So far we received over 20 patients, including several critical cases. Patients with burns were also admitted. We are providing surgical services and wound dressing, along with other emergency care," MSF's Christian Lindauer, the charity's manager at the hospital, said in a statement.
Meanwhile, a drone strike near the airport in Khartoum on Monday has killed four people, including three children, the AFP news agency reports, quoting a medical source.
It also cited a military source as saying air defences in the Sudanese capital had downed several other drones launched by the RSF towards the airport.
Fighting in Kordofan, a strategic area rich in gold and oil, has intensified over the last year after the army regained control of Khartoum from the RSF.