"Another appalling attack" on a hospital in Sudan has seen more than 40 people killed, many of them children and medics, the head of the World Health Organization (WHO) has said.

"We cannot say this louder," wrote Tedros Adhanom Ghebreyesus on X on Tuesday, "attacks on health must stop everywhere!"

Al-Mujlad Hospital was struck on Saturday, and is located in West Kordofan state, close to one of the frontlines where Sudan's warring parties are fighting in the conflict that is now in its third year.

The Rapid Support Forces (RSF) blames its opponents the Sudanese army for attacking the hospital, as do two prominent civil society groups, but the army itself has yet to comment on the allegation.

Since Sudan's civil war began in April 2023, the scale of suffering is so vast that the UN has labelled it the world's worst humanitarian crisis.

In addition to allegations of genocide in Darfur, the murder of many thousands of civilians across the country, plus the displacement of millions more, both sides in this conflict have been accused of carrying out war crimes on medical facilities and staff, according to evidence seen by BBC News Arabic.

Al-Mujlad Hospital, in the town of Muglad, was "the only functioning healthcare facility in the area", according to the Sudan Doctors Network.

Of the more than 40 people killed, six of them were children and five were health workers, the WHO's office in Sudan said on Sunday. Dozens of other people were injured too, it added.

Crucially, the hospital ran a dialysis unit and focused on the care of civilians as opposed to soldiers, according to the Emergency Lawyers group, which documents abuses by both the RSF and the army.

Both the Sudan Doctors Network and the Emergency Lawyers group say the Sudanese Armed Forces (SAF) were to blame for the attack on Saturday.

But the doctors' body says the reason for the attack was that the army was trying to kill RSF fighters "stationed inside" al-Mujlad Hospital. The RSF has not commented on that claim, nor has the army.

On Monday, the head of the UN children's agency, Unicef, warned of a "worsening crisis" for children caused by Sudan's civil war and said the aid response lacked two-thirds of the funding needed.

Visiting refugees in neighbouring Chad, Catherine Russell said "hundreds of thousands of the most vulnerable children are bearing the brunt of both the war in Sudan and a lack of essential services for those who have fled to Chad".

Many children are "malnourished, out of school, and at serious risk of exploitation and disease", she added.

Among the most harrowing accounts to come out of Sudan's war is the evidence that armed men are raping and sexually assaulting children as young as one. Some children have tried to end their own lives as a result.