Los Angeles: At least six homes in one of Los Angeles wealthiest suburbs - the iconic Bel Air - have been destroyed and a winery owned by media mogul Rupert Murdoch is under threat as a firestorm in California burns out of control.

Part of Murdoch's Moraga Bel Air vineyard, where the 86-year-old Australian has a home, has been destroyed by fire, and it is one of a number of properties affected by a mandatory evacuation order, issued by emergency services today.

The fires have also closed one of America's busiest freeways - the traffic-choked 405 - with video emerging of one of the four fires reaching the edge of the freeway.

The pre-dawn sky of Los Angeles was lit bright orange with fire as traffic moved at a slow, silent crawl past the inferno until police made the decision to close a 15km stretch of the freeway because of the risk.