The battery spontaneously combusted while stored in a luggage in the overhead bin. The airline said there were no injuries.

It seemed that last year’s wildfire in Los Angeles had been extinguished safely after two days. But it had just gone underground.

Readers respond to a guest essay about vaccine debates. Also: Attorney General Pam Bondi’s performance; wildfire smoke and our health.

Across the country, unmasked wildfire fighters are falling ill and dying. Hannah Dreier talks about her investigation into the risks these workers face.