At least 22 people were killed and scores injured in an air strike by Sudan's army on western Omdurman, the Khartoum state health ministry said on Saturday, as the war between the country's military factions entered its 12th week.

While the paramilitary Rapid Support Forces (RSF) quickly dominated the capital Khartoum and its sister cities Omdurman and Bahri after fighting broke out on April 15, the army has launched air and artillery strikes.

The fighting, for which no mediation efforts have succeeded thus far, threatens to drag the country into a wider civil war, drawing in other internal and external actors in the East African nation that lies between the Horn of Africa, Sahel, and Red Sea.

Tensions between both sides had grown in the months leading up to the war over the chain of command and integration of their forces under a new transition to democracy.

At least 1,133 people have been killed in the fighting, according to the federal health ministry, which has flared in the capital and the Kordofan and Darfur regions, sparking ethnic violence in West Darfur state.

More than 2.9 million people have been uprooted, including nearly 700,000 who have fled into neighbouring countries. More than half of the capital has

It has also caused "alarming numbers" of rape and abduction of women and girls, according to aid agencies.

Fighting has focused on Omdurman in recent days, as the western part of the city is a key supply route for the RSF to bring reinforcements in from Darfur, its power base.

Strikes, including overnight on Friday, have also centred on the country's state broadcasting complex in eastern Omdurman. Other overnight strikes hit southern and eastern Khartoum.

The army said in a post on Facebook that special forces had killed 20 "rebel soldiers" and destroyed their weaponry.