WINSTON-SALEM, N.C. (NewsNation Now) — An uncontrolled fire raging at a North Carolina fertilizer plant forced the evacuations of thousands of people as firefighters warned Tuesday that chemicals at the site could cause a large explosion.

Authorities drove through neighborhoods and knocked on doors asking residents within a one-mile radius of the Weaver Fertilizer Plant to leave. The fire started Monday at 6:30 p.m. local time at the plant on the north side of Winston-Salem. No injuries or deaths had been reported as of Tuesday afternoon, according to Andrew Carroll, a representative of the Winston Weaver Co.

Carroll said they would continue working with first responders and relevant officials to ensure the safety of the community, and the plant will participate fully in the investigation into the cause of the fire.

Most of the campus of Wake Forest University is just outside the evacuation zone. The university urged students living in dormitories to stay indoors and keep windows closed.

Bright orange flames could be seen shooting into the sky along with thick plumes of smoke as lights from firetrucks and other first responder vehicles surrounded the fully engulfed building. The evacuation area included about 6,500 people in 2,500 homes, the Winston-Salem Fire Department said.

“We fought the fire for two hours and the fire extended into a rail car behind the structure. Once the railcar became involved, we were unable to get water to the location, and has a large explosive hazard,” Winston-Salem Battalion Chief Patrick Grubbs told NewsNation affiliate WGHP-TV early Tuesday.

Firefighters had pulled back from the scene due to the danger of the uncontrolled fire, leaving behind an unmanned truck to pump water on part of the site, Grubbs said. Authorities were also flying drones over periodically to assess the fire.

“We want to make sure that right now we’re evacuating everybody in this one-mile radius,” Grubbs said. “There is still a potential for explosion.”

At least 90 firefighters fought the fire for about 90 minutes after it was discovered at a loading dock around 7 p.m. Monday, authorities said. But Winston-Salem Fire Chief Trey Mayo said fire crews were pulled back because of the large volume of ammonium nitrate on site. The fire department has said that firefighters could not flow a large enough volume of water to be reasonably certain that they could keep it cool enough to prevent a detonation.

Grubbs warned that there would be a lot of smoke and poor air quality. He said that it could take some time for the fire to come under control.

Michelle Shepherd, who lives blocks from the plant, told the Winston-Salem Journal that after hearing and feeling explosions and seeing the flames Monday night, she didn’t wait for the evacuation order to leave her house and head to a shelter opened by local authorities.

“We felt big explosions. The entire house shook,” she told the newspaper. “And I looked out my front door and I could see the orange glow.”

Less than two miles away, Wake Forest canceled classes for Tuesday and opened a campus building for students and staff who live off campus but had to relocate. The university said only one campus housing building was within the evacuation zone.

The Forsyth Correctional Center, a minimum-security prison with a capacity for about 250 inmates, also is in the evacuation area.

Winston-Salem officials said a shelter has been set up at the Winston-Salem Fairgrounds. People who have evacuated should plan to be away from their homes for up to 48 hours.

The fertilizer plant was closed when the fire started and no employees were inside, local media outlets reported.

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