The Cypress Creek Fire Department stated that at least five agencies responded to the facility on Windfern near Gessner at about 1:30 a.m.
Dist. Chief Lance Wilson said they had firefighters on rotation to avoid overheating, with the added issue of summer temperatures.
Although precautions were in place to keep these firefighters safe, Cy-Creek Fire says two still had to be treated.
One firefighter was treated for ant bites, and the other for heat exhaustion. Authorities stated that both later returned to work.
Eyewitness News was informed by one of the facility's owners that it was a basic storage unit that didn't cater to any particular item or specialty.
Wilson said at least 16 units burned, and the fire was extinguished at about 3:20 a.m.
The cause of the fire is still under investigation.
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