Mandatory evacuations are expanding as a wildfire burns in the foothills of a national forest east of Los Angeles. Tens of thousands of homes and other buildings are being threatened by the so-called Line Fire. The blaze was burning uncontrolled along the edge of the San Bernardino National Forest, about 65 miles east of LA. As of Sunday morning, the blaze had charred about 27 square miles of grass and chaparral. The cause is under investigation. More than 600 firefighters were battling the blaze, along with water-dropping helicopters and other aircraft. Temperatures in the area were expected to soar into the triple digits as Southern California experiences a days-long heat wave.