In the case of the Eaton Fire, the investigators are likely to use magnets to help them hunt for the tiny, melted pieces of metal that could have been shed by power lines if they slapped together. But the existence of the metal doesn’t necessarily indicate that’s how the fire started, Nordskog said.

Since destructive wildfires broke out in Los Angeles on Jan. 7, at least 11 people have died and thousands have been displaced.