A Medevac helicopter crashed, killing the pilot and two crew members, authorities said. The accident occurred Sunday evening as the Bell 412 utility helicopter left from Loma Linda Medical Center to its base in Victorville, said Ian Gregor, a spokesman for the Federal Aviation Administration. The pilot may have encountered fog in the Cajon Pass before the helicopter crashed and burned, Gregor said. All three crew members aboard were killed. Their identities were not immediately released. No patients were aboard the aircraft, Gregor said. Authorities initially said there was the possibility the aircraft clipped some power lines but later said they saw no signs of downed lines. The cause of the crash is under investigation. Devore is 55 miles (90 kilometers) northeast of Los Angeles.