(AP) Federal authorities say another mild earthquake has occurred under central Nebraska. The U.S. Geological Survey says the latest occurred around 6:40 p.m. Sunday about 3 miles under the surface 20 miles east-southeast of Stapleton, not far from Arnold. Stapleton is almost 4 hours northwest of Lincoln. Sunday’s quake was rated a 2.6 magnitude temblor…the area’s 5th quake in a week. No damage or injuries have been reported.