A large fire that broke out at an oil supply and logistics company in Williston, North Dakota has been extinguished.

The blaze, which ignited in an oil patch hub in the western part of the state, grew so hot that fireballs shot hundreds of feet into the air. The fire started at around midnight Monday, and Williston Fire Department shift captain Steven Kerzmann said that it is still unclear what caused the blaze. Fire trucks from neighboring towns Ray and Epping assisted in controlling the fire, and three of the five buildings at the site were saved.

Red River Supply owns the facility, and the company says it provides storage, blending and delivery of oil drilling fluids, soil stabilization materials, dust control products and proppants. North Dakota state records show that various flammable chemicals were stored at the site of the fire.

Kerzmann commented that the majority of firefighters who battled the blaze left Tuesday evening, though one truck remained at the site to monitor hot spots. “The fire is out, but you’ve got some smoldering embers that might pop up here and there,” Kerzmann said. Red River Supply said that no one was injured in the fire.

#USAnews #USnews Officials probe fire at North Dakota company: WILLISTON, N.D. (AP) — Federal and state invest… http://t.co/hLN4y5Tb3f

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Williston Fire Chief Jason Catrambone said officials have yet to identify which specific chemicals had burned at the site, though Williston Mayor Howard Klug said a hazmat unit monitoring air quality found nothing potentially harmful. Tim Wiedrich, a spokesman for the North Dakota Department of Health, said the agency is also monitoring air quality around the site.

Flights were restricted from Williston’s Sloulin Field International Airport until 2 p.m. Tuesday, according to airport manager Steven Kjergaard. The Federal Aviation Administration issued the six-hour restriction due to concerns over the massive pillar of smoke rising from the still-smoldering site.

Local police initially evacuated everyone within a half-mile of the blaze, and traffic in the area was diverted. The perimeter has since been downgraded to two blocks from the Red River Supply facility.

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