Aftershocks kept Hawaiians on edge following the strongest earthquake in more than two decades, a 6.6-magnitude quake that caused blackouts, landslides and prompted vacationers to flee their hotels. There were no reports of fatalities, but the state Civil Defense had several reports of minor injuries. Gov. Linda Lingle issued a disaster declaration for the state. The quake hit at 7:07 a.m. local time Sunday, 10 miles north-northwest of Kailua-Kona, a town on the west coast of Hawaii Island, also known as the Big Island, said Don Blakeman of the National Earthquake Information Center, part of the U.S. Geological Survey, the Associated Press reported.