Saturday's attack by the Rapid Support Forces occurred close to the city of Rahad in North Kordofan province, said the Sudan Doctors Network, which tracks the country's ongoing war. The vehicle was transporting displaced people who fled fighting in the Dubeiker area, the group said in a statement. Among the dead children were two infants.
Several others were wounded and taken for treatment in Rahad, which suffers severe medical supplies shortages, like many areas in the Kordofan region, the statement said.
The doctors' group urged the international community and rights organisations to "take immediate action to protect civilians and hold the RSF leadership directly accountable for these violations."
There was no immediate comment from the RSF, which has been at war against the Sudanese military for control of the country for about three years.
Sudan plunged into chaos in April 2023 when a power struggle between the military and the RSF exploded into open fighting in the capital, Khartoum, and elsewhere in the country, leaving tens of thousands dead and millions displaced.
An attack on Friday on WFP aid convoy in North Kordofan province, which killed one and wounded several others, said Denise Brown, the UN humanitarian coordinator in Sudan.
Brown said the convoy was heading to deliver "life-saving food assistance" to displaced people in the city of Obeid in North Kordofan when it was struck. The attack burned the trucks and destroyed the aid, she said.
"Attacks on aid operations undermine efforts to reach people facing hunger and displacement," he said in a statement.
Last week, a drone strike hit close to a WFP facility in the Blue Nile province, wounding a WFP worker, Brown also said.
Emergency Lawyers, an independent group documenting atrocities in Sudan, blamed the RSF for the attack, while the Sudan Doctors Network called it a "flagrant violation of international humanitarian law and amounts to a full-fledged war crime."
Massad Boulos, a US adviser for African and Arab affairs, condemned the attack on X and called for holding those responsible accountable.
"Destroying food intended for people in need and killing humanitarian workers is sickening," he said.
"The Trump Administration has zero tolerance for this destruction of life and of US-funded assistance; we demand accountability."
The British minister for international development and Africa, Jenny Chapman, called the attack on the WFP convoy "disgraceful."
"Civilians are starving," she wrote Saturday on X.
"Aid workers and humanitarian operations bringing vital food should never be targeted."
In recent months, Kordofan has become a flashpoint in the war and the army managed to break the RSF siege of two major cities in the region earlier this year.
The devastating war has so far killed more than 40,000 people, according to UN figures, but aid groups say that is an undercount and the true number could be many times higher.
It created the world's largest humanitarian crisis with over 14 million people forced to flee their homes. It has fueled disease outbreaks and pushed parts of the country into famine that still spreads as the war shows no sign of abating.
And in a report released Thursday, the Integrated Food Security Phase Classification, or IPC, confirmed famine in two more areas in Darfur and warned acute malnutrition was expected to worsen in 2026.
