WINDSOR, Colo. (CBS4) – Emergency crews spent all night battling a fire that resulted from an explosion at an oil and gas facility in Weld County.

(credit: CBS)

The explosion happened just before 9 a.m. just outside of Windsor along Highway 392.

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People nearby said the explosion shook their homes.

“I was standing outside of my house and all of a sudden I heard two explosions,” one neighbor told CBS4.

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At least one person who was at the site was rushed to the hospital and there’s no word on their condition. They haven’t been identified.

Authorities say fires at drill sites are rare and require special attention.

“Oil sites are kind of technical because they could be drilling for a variety of things — crude oil, natural gas, propane, things of like that,” said Todd Vess, spokesman for Windsor Severance Fire Rescue. “So we (worked with them) and came up with a plan of attack as far as what we could and couldn’t put water on, where to start attacking it from.”

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An investigation is underway to determine what sparked the explosion and to figure out what was burning.