What started as the wind-driven wildfires common in California escalated into fast-moving infernos, roaring through homes and sending thousands fleeing in the middle of the night.

More than 1,000 people are unaccounted for and thousands of survivors are living in cars and tents as California's deadliest wildfire enters a second week.

Due to the wildfires raging in Northern California, San Francisco, Stockton and Sacramento were the world's three "most polluted cities" on Friday morning, according to Berkeley Earth, a nonprofit that aggregates data from air-quality monitoring sites.

In an interview with Fox News, President Donald Trump suggests poor land management is more to blame for raging wildfires in California than climate change.

These images show the extent of devastation from the deadliest and most destructive wildfire in California history.

Major wildfires in California have destroyed a record number of buildings and displaced more than 300,000 people.

With the shocking loss of thousands of homes and dozens of lives in the Camp and Woolsey fires in Northern and Southern California, people are looking for answers as they try to understand how a tragedy such as this can be prevented in the future.

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