The number of deceased people has increased to 10 as authorities and the medical examiner continue to respond to reported fatalities.

Rows of cars at a dealership, blasted by flames, looked like they had been bombed. A man wearing a mask walked by debris of a neighborhood destroyed. A couple, arms around each other, looked at what was left of their smoldering home. A statue of a human, without a head, lay on a street.

It is not yet known what sparked the wildfires, although power cables blowing in the wind are a likely cause. But three factors made the conflagration blow up. We explain.