According to authorities, the fire started around 3 a.m in the 2900 block of FM 1960.
Firefighters say it appears that someone forced open a back door to the building.
Deputies say there were fireworks in the store at the time, but not enough to be a danger to the area.
HCFMO investigators are investigating a fire at a fireworks store in the 2900 block of FM 1960. One firefighter was treated for a knee injury and heat exhaustion. Very few fireworks were onsite at the time of the fire. The fire is under investigation. More info when available. pic.twitter.com/7dR9SvdcFa— Harris Co. FMO (@hcfmo) July 24, 2019
One firefighter was injured and taken to the hospital.
Authorities haven't said how the fire may have started.
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