York County deputies said the fire was not actually at the fireworks store but started in containers just outside the store.
Viewer video sent to WSOC showed the fireworks shooting into the sky and exploding just before dawn.
Captain Jeff Nash with the Flint Hill Fire Department said the fireworks were still exploding in the containers when firefighters got to the scene, creating a dangerous environment.
"The challenge is knowing what you can trust and what you can't trust," Nash said. "There definitely is a risk."
It took about 45 minutes to get the fire knocked down.
Nash said the storage containers were on the property of the Davey Jones Fireworks Store but that there was no damage to the building. Nash could not put a dollar value on the fireworks that went off but said the boxes appeared to be fully loaded.
Officials said no firefighters or civilians were injured.
There is no word on how the fire started and the York County Fire Marshal was headed to the scene to investigate the cause.
Carowinds Boulevard from Highway 51 to the I-77 exit ramp was closed as crews worked to put out the flames but was reopened around 7 a.m.
Check back with wsoctv.com for updates on this story.
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