(AP) — An initial synopsis on an Arizona wildfire that began with a lightning strike and caused little immediate concern shows how the blaze quickly turned into an inferno due to extreme weather and wind.

The fire began June 28 outside the small town of Yarnell about 60 miles northwest of Phoenix. It destroyed more than 100 homes before it was fully contained on July 10. Nineteen members of an elite Hotshot firefighting crew died when they were overtaken by flames.

A national team of investigators is working to understand more about the firefighters’ deaths and is expected to finish an initial report in about two months.

The synopsis, released Monday, spells out how the blaze grew from a mere acre to a fast-moving inferno within 36 hours, trapping the firefighters and cutting them off from their safety zone.