A drone attack on the town of Kalogi, in Sudan's South Kordofan region, is said to have hit a kindergarten and killed at least 50 people, including 33 children.

The Rapid Support Forces (RSF), the paramilitary group battling the army in Sudan's civil war, was accused of Thursday's attack by a medical organisation, the Sudan Doctors' Network, and the army.

There was no immediate comment from the RSF.

The RSF in turn accused the army of hitting a market on Friday in a drone attack in the Darfur region, on a fuel depot at the Adre border crossing with Chad.

Sudan has been ravaged by war since April 2023 when a power struggle broke out between the RSF and the army, who were formerly allies .

The reports could not be verified independently.

According to the army-aligned foreign ministry, the kindergarten was struck twice with missiles from drones.

Civilians and medics who rushed to the school were also attacked, it added.

Responding to reports of the attack in Kalogi, a spokesman for the UN children's agency Unicef said: "Killing children in their school is a horrific violation of children's rights."

"Children should never pay the price of conflict," Sheldon Yett added.

The agency, he said, urged "all parties to stop these attacks immediately and allow safe, unhindered access for humanitarian assistance to reach those in desperate need".

The RSF accused the army of attacking the Adre crossing because it was used for the "delivery of aid and commercial supplies".

According to the Sudan War Monitor, a group of researchers tracking the conflict, the attack caused civilian casualties and significant damage to a market.

The military did not immediately comment on the reports from Darfur.

Wedged between Sudan's capital Khartoum and Darfur, the region made up of North Kordofan, South Kordofan and West Kordofan has been a frontline in the civil war.

The battle for the Kordofans - which have a population of almost eight million - has intensified as the army pushes towards Darfur.