Rockets hit a market in Sudan’s capital, Khartoum, killing 18 people and leaving more than 100 wounded, doctors and residents say.
The fighting between rival military forces comes as truce talks mediated by the US and Saudi Arabia collapsed.
Wednesday’s violence around a market in Mayo in the south of Khartoum included artillery fire and aerial bombardment.
It caused the most civilian casualties in a single incident in the capital since the war began in April.
This brings the civilian death toll over seven weeks to at least 883, according to official counts – though the real number is likely to be far higher.
Neighbourhood organisations – which have been helping Khartoum’s residents get food and medicine – described it as a catastrophic situation and appealed for doctors and blood donations.
According to the UN, 25 million people, more than half the population of Sudan, are now in need of humanitarian aid and protection.
With talks no longer taking place there is a fear of the fighting escalating as heavy fire was reported this morning across the River Nile from Khartoum in the cities of Bahri and Omdurman.
The UN World Food Programme (WFP) says its warehouses in El Obeid in North Kordofan state, with food for 4.4 million people, are coming under attack