Authorities say the man was working with the flare gun and fireworks at a home on 200 block of Oaks Grande Drive the Baytown area.
Investigators believe 52-year-old John David Cook Jr. was experimenting with fireworks, something his wife told authorities her husband doesn't typically do.
As the last minutes of Christmas were ticking away, the quiet in a Chambers County neighborhood came to an end.
"It was like ka-whoom!" neighbor K.R. Harrison said.
The explosion was so powerful, Harrison says, it set off car alarms and shook the ground. It also killed Cook.
"We didn't think it was going to be good," Harrison said.
"It appears he was trying to make a bigger boom," Chambers County Sheriff Brian Hawthorne said.
Investigators believe Cook was building a larger explosive device from fireworks and using a 37mm launcher when things went wrong. They believe he was attempting to fire it in the backyard of his home when it exploded in his hands.
"Both of [Cook's hands] were severely injured, one was severed. And then it appears that part of the device he was trying to build impaled in his chest," Hawthorne said.
Cook's wife, who had been asleep, called 911. He died on the way to the hospital.
Sheriff Hawthorne has this warning:
"Fireworks are extremely dangerous and particularly if you don't use them for what they are designed for," Hawthorne said.
While it is legal to set off fireworks in Chambers County, it is illegal to modify. Doing so, the sheriff says, cost Cook his life.
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