The Lake Fire, blazing about 65 miles north of Los Angeles near Lake Hughes and amid a dangerous heat wave that has caused rolling blackouts in some parts of the state, has burned 18,361 acres as of 7 p.m. PDT Sunday, according to the Angeles National Forest. It has destroyed 12 structures and 21 outbuildings. More than 4,500 structures remain threatened by the fire. The fire is 12% contained with no known cause. No injuries have been reported