evidence: In just over a week, the volatile components behind Sudan’s division into two nations — oil, religion, ethnic rivalry, guerrilla militias, disputed borders — have burst into war. TIME photographer Dominic Nahr has been on assignment in South Sudan’s ironically named Unity State, whose northern edge includes disputed boundaries with its enemy Sudan — one of which is marked only by a white cargo container. In the last nine days, South Sudan forces have pushed north into Sudanese territory, taking the disputed town of Heglig, only to pull back under fire and see enemy soldiers press south instead. Nahr filed this dispatch on Sunday. [...] No one seems to know what’s going on and when I try to reach the front lines I mostly get stalled or put-off by soldiers, commanders and officials. In the end I hitched a ride with southern soldiers to Heglig, a disputed town that South Sudan occupied for a few days. They were less concerned with the fighting than they were with filling the pick-up truck with looted beds, mattresses, laptops and printers from the town. On another drive the hood of our truck, which was held on with rope, flipped up and smashed the windscreen as we flew down a rutted dirt road.