Hundreds of thousands of people have been displaced internally or have fled to South Sudan because of the fighting.
Because Sudan has barred Amnesty International from entering the country since 2006, the report is based on interviews with refugees from Southern Kordofan at Yida and Pariang refugee camps in Unity State, South Sudan, and on people who live in SPLA-N controlled areas of Southern Kordofan
"Many of those to whom Amnesty International spoke in Southern Kordofan, including people who had lost family members and/or suffered injuries, had left their homes and sought shelter in caves and surrounding areas," the report says.
The report tells of a nursing mother being bombed in her home by SAF planes, of fathers who lost their children to bombs, of an elderly woman who saw her neighbors "cut into pieces" in a bombing raid.
"I picked up her parts to bury. Amal was cut into two and was pregnant…We cannot endure this anymore. It has to end. Stop the planes,” the old woman said in the report.
Because the bombing raids disrupt farming activity, Amnesty International warned that the "majority of internally displaced people are likely to face crisis levels of food security by the time the rainy season starts in the next few weeks."