An air strike by Sudan's army killed 22 people and injured dozens of others in the city of Omdurman adjoining the capital Khartoum, the Sudanese Health Ministry said on Saturday.
The army has carried out repeated air strikes against the rival paramilitary Rapid Support Forces since the two sides began fighting nearly three months ago. The conflict has been centred on the capital Khartoum as well as North Kordofan and the vast western region of Darfur, where the UN has warned of possible "crimes against humanity".
Both sides have ignored ceasefires called to allow civilians to seek safety and the delivery of humanitarian aid. The RSF has established bases in residential areas while the army has struggled to take advantage of its air superiority.
Residents on Friday reported air strikes in the area of the state broadcaster's headquarters in Omdurman and anti-aircraft fire to repel the raids. Another witness reported an air strike on an RSF base in northern Khartoum.
Many civilians have accused the RSF of carrying out acts of violence against them, while also charging that the armed forces have done little to protect them. The fight for supremacy between the paramilitary group led by Gen Mohamed Dagalo and the Sudanese army under Gen Abdel Fattah Al Burhan has claimed the lives of at least 3,000 civilians and displaced millions.
On Friday, RSF fighters attacked a remote town in North Kordofan province before "looting banks and public buildings", residents said.
"We're being terrorised: they shoot and loot, and the army and police are nowhere to be seen," said Abdelmohsen Ibrahim, a resident of Bara, 50km north-east of El Obeid, the capital of North Kordofan.
"Even if the army tries to come from El Obeid, the RSF are in control of the El Obeid-Bara road."
The paramilitary group has been accused of forcing civilians out of their homes, seizing their vehicles, robbing them and raping women as they flee to neighbouring countries.
Save the Children said on Friday that teenage girls were being sexually assaulted and raped by armed combatants in "alarming numbers".
While dozens of cases of rape resulting from the conflict have been verified, the Sudanese government's Combating Violence against Women (CVAW) unit estimates that figure may represent only 2 per cent of the total.
"We know that the official numbers are only the tip of the iceberg. Children as young as 12 are being targeted for their gender, for their ethnicity, for their vulnerability," Save the Children's Sudan director Arif Noor said.
Some parents were marrying off their daughters at a young age to try to protect them from further abuse, he said.
There have also been reports of girls being held for days while being sexually assaulted, and gang rapes of women and girls.
"Healthcare providers, social workers, counsellors and community-based protection networks inside Sudan have all warned of a marked increase in reports of gender-based violence as hostilities continue across the country," United Nations agencies said in a joint statement this week.
"Reporting violations and getting support is also made difficult, if not impossible, by the lack of electricity and connectivity, as well as lack of humanitarian access due to the volatile security situation."
CVAW also reported an escalation in cases of abduction of women and girls, especially in Khartoum, citing several recent cases for which it said RSF fighters were responsible.
The RSF has not directly addressed accusations of assault and sexual violence by its fighters, but has said that those who commit abuses will be held to account.
The paramilitary group traces its origins to the Janjaweed, feared Arab militiamen who committed widespread atrocities against non-Arab ethnic minorities in Darfur starting in 2003.
Meanwhile, the east African regional bloc IGAD said that a meeting of heads of state tasked with resolving Sudan's crisis would be held in the Ethiopian capital Monday, the bloc's spokesman Nour Mahmoud Sheikh Al Jumaa said.
An IGAD official, speaking on condition of anonymity, said that both Gen Al Burhan and Gen Dagalo had been invited to the summit.
"They may attend or send high-level representatives," the official said.
Agencies contributed to this report.