The houses were ignited by embers from the wildfire upwind. Trees cannot, in general, be ignited by embers. Some trees burned because they were close to houses that burned. Cars were mainly ignired by flames. The burned cars that I saw were mostly near houses or flammable vegetation or other burning items.
Basically the town was hit by an ember storm from wildfire upwind which was driven by brush (ladder fuel) and fully burning trees. Was it possible that some locations were burned intentionally/? Anything is possible. It's not likely. It is likely that they had to let a lot of houses burn because there were far too many to put out. The firefighters were mainly doing rescue only at that point.
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Nonsense!
Go look for yourself.
There’s even still brush on the ground next to houses that burned.
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The houses were ignited by X-ray lasers from the air.
They use the laser to heat appliances inside the house, which then ignite the frames of the houses.