Hospitals were shelled, doctors say. Damage was reported at al-Shab Teaching Hospital in Khartoum along with two other clinics.
The fighting is between army units loyal to the de facto leader, Gen Abdel Fattah al-Burhan, and the RSF, a notorious paramilitary force commanded by Sudan's deputy leader, Mohamed Hamdan Dagalo, better known as Hemedti.
Hemedti said on Monday that the international community must intervene, and branded Gen Burhan "a radical Islamist who is bombing civilians from the air". Gen Burhan has said he is willing to negotiate.