A wildfire in the hills near Los Angeles exploded overnight, torching dozens of homes as its footprint swelled 1,000% by Wednesday.

The Bridge Fire is one of three out-of-control blazes that have erupted around the United States' second-biggest city, fueled by a punishing heat wave and fanned by gusting winds.

Authorities issued widespread evacuation orders as the fire tore through the towns of Wrightwood and Mt. Baldy, destroying at least 33 homes, several cabins, and racing through a ski resort.