A tornado ripped across southwestern Indiana and northern Kentucky early Sunday, killing at least 17 people, wrecking homes and knocking out power to thousands, authorities said. The death toll was expected to grow, they said. About 200 people had been injured. Witnesses said the tornado touched down first near Henderson, Kentucky, and hopped across the Ohio River into Indiana at around 2 a.m. No deaths were reported in Kentucky, said Michelle King, a dispatcher with the Henderson County sheriff's office. Mike Roeder, a spokesman for utility company Vectren, said 25,000 homes were without power, mostly in Warrick County. There also were reports of natural gas leaks. The tornado developed in a line of thunderstorms that rolled rapidly eastward across the Ohio Valley during the morning.