UN agency denied access in Sudan border area
Humanitarian flights denied permission to land in Kordofan capital and roadblocks hampering land access
South Sudan accuses north of second airstrike
Southern Kordofan state seen as a flashpoint in the build-up to the split because it is home to thousands of fighters who sided against Khartoum during the last civil war
FACTBOX: What's the impact of 'hidden hunger'?
A lack of vitamins and minerals in the diet can result in blindness, stunted growth, disease and even death
Over 53,000 flee Sudan border state - UN
Humanitarian organisations fear a mounting death toll although few casualties have been confirmed so far