(KMOV) -- Fireworks sparked a fire near the Simpson Quarry on Sunday.
Investigators say the fire started around 1:00 p.m. on Sunday in Jefferson County.
The flames set between 200,000 and 300,000 pounds of mulch ablaze.
Firefighters eventually put some water on parts of the mulch, after carefully clearing away parts of the piles.
Firefighters with the Rock Community Fire Protection District worked on this fire for several hours.
It was finally extinguished around 2:30 p.m. Monday.
Authorities say they found firework shells near the mulch and investigators say they're certain that's what sparked the fire.
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