(CNN) -- Though an in-depth report released Saturday assigned no blame in the death of 19 elite Arizona firefighters, it did raise some key issues about the day the men died.
The firefighters, known as the Granite Mountain Hotshots, died on June 30 fighting wildfires in Arizona. The fire was started by a lightning strike, rapidly spread from one-half acre to several hundred and destroyed more than 100 structures. It took the lives of the 19 hotshots before it was contained.
The interagency report, commissioned by the state, detailed what went wrong in the Yarnell Hill Fire and made recommendations to improve the future safety and efficiency of fire crews, both in Arizona and nationwide.
The report found the crew was fully qualified, staffed and trained.
But it said fire personnel dealt with radio communications issues throughout that day.
Earlier in the day, the crew had been in one area, but later moved from that point, and officials said they may never know why.
"We have no indication that Operations or anyone else asked the Granite Mountain IHC to move to a new location but we assume they decided this on their own, believing they could reengage and help defend Yarnell," officials said in the report.
The Yarnell Hill fire was discovered on the evening of June 28. Due to the dangerous terrain and the small amount of fire seen at that point, officials said the decision was made not to put fire personnel in the area at that time. The next morning, the fire had grown to several hundred acres, was moving toward the town of Yarnell.
Fire retardant was dropped on the area and some firefighters were dispatched, according to the report.
The hotshot team was deployed the morning of June 30. The day started with some radios not being programmed with the correct fire tones, which the firefighters were able to work around, officials said. The team then had about a 45-minute hike into the anchor point, which is the spot where they began their efforts.
According to the report, the hotshot team received several weather reports from the National Weather Service during the day; the reports warned of approaching storms and changing wind speeds and directions.
What we now know, from the report, is that the hotshot crew was on top of a ridge and making its way to a designated safety zone when the winds changed erratically again, causing the fire to split and accelerate dramatically, trapping all 19.
The officials who spent more than three months compiling the 116-page report personally delivered it to the families of the hotshot team before releasing it to the media and the public Saturday.
Not since September 11, 2001, had the nation lost so many firefighters in one day.
Gov. Jan Brewer said the deaths represented "as dark a day as I can remember." A 100-mile procession brought their bodies from the state Capitol, through the community where they perished and back to their hometown of Prescott. Their loss felt especially acutely there as the 19 represented 20% of the city's fire department.
Vice President Joe Biden spoke at a memorial service attended by thousands. The Granite Mountain Hotshots realized, Biden said that integrity "is measured by whether you respond to the needs of your neighbors."