It was a 33,000 gallon railroad car full of propane that burst into flames near the center of town, and changed the community of Kingman forever.
July 5, 1973 was one of the worst days in Arizona history. Eleven firefighters were killed, including William Casson.
Mike Casson said it was hard growing up without a father.
"I think about it all the time," said Casson. "It sticks with me. It's still very vivid in my mind. My mom took over the responsibilities of taking care of all of us. She was a saint, and helped us all get through this thing and carry on with our lives. The kind of person he was, had a lot to do with who I became, and who I am."
Most of the firefighters killed that day were volunteers, well entrenched within the community, a high school principal, state policeman, local business owners.
The tragedy left a lot of children to grow up without a father.
A gas company worker was also killed, and more than 100 people injured.
Kingman Fire Chief Chuck Osterman said that seeing what happened at the Yarnell Hill fire this week, where 19 firefighters died, brought back a lot of tough memories.
"Obviously, for those of us that were affected by the tragedy 40 years ago, you immediately feel and know how the community of Prescott is feeling, because we went through it," said Osterman. "I think it was surreal that it happened in that time frame, but extremely impact for us."
A special ceremony will be held Friday night at 6pm, at Firefighter Memorial Park in Kingman, to honor the firefighters who lost their lives 40 years ago Friday.
Their loved ones may be gone, but will never be forgotten.
"As each year goes by, it certainly eases the pain a little bit," said Casson.
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