Khartoum under siege as fighting spreads across Sudan

Battles have been raging in Sudan's war-torn capital of Khartoum since last Tuesday with no sign of the violence abating. Other regions are also experiencing prolonged battles, especially Darfur.

Witnesses described "the sound of heavy artillery fire" in northern Khartoum, and "clashes with various types of weapons" in south Khartoum.

In the city centre, at the confluence of the White Nile and Blue Nile riv