Hawaii volcano erupts in 6-mile-high plume, 'ash fallout' alertBy Terray Sylvester PAHOA, Hawaii (Reuters) - Hawaii's Kilauea volcano spewed ash nearly six miles (30,000 feet/9 km) into the air on Thursday and scientists warned this could be the first of a string of explosive eruptions in the crater. "This has relieved pressure temporarily," U.S. Geological Survey geologist Michelle Coombs told a news conference in Hilo. "We may have additional larger, powerful events." Residents of the Big Island were warned to take shelter from the ash as toxic gas levels spiked in a small southeast area where lava has burst from the ground during the two-week eruption, authorities said.