chemical fire illinois
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A huge blaze at a chemical plant in Rockton, Illinois may not burn out for several days, the local fire chief has warned. People living within a two-mile radius of the site have been evacuated from the area.

The fire was reported at around 7am local time (8am ET) on Monday at Chemtool Incorporated in Rockton, according to local media.

Rockton Fire Department ordered the mandatory evacuation, and drivers have also been told to avoid the area.

Dramatic eyewitness footage from the scene showed a huge explosion and mushroom cloud at the site, which is close to the Illinois-Wisconsin state border.

Enormous clouds of black smoke and large flames could also be seen rising up from the building. The scale of the smoke was such that it could be seen by plane and via satellite imagery.

There have been reports of ash from the plant falling in the Rockton area and the city of Rockford to the south. A reporter for local broadcaster 13WREX posted pictures of charred debris, which was said to have landed in people's backyards.

Rockton Fire Chief Kirk Wilson said 70 plant employees were evacuated from the building prior to the arrival of fire crews. One firefighter, who sustained minor injuries and walked to an ambulance, was the only injury reported, he told a press conference.

Wilson also said there is "no danger" to air quality at ground level, explaining that the evacuation zone was a "precautionary measure."

He said the plan now is to let the oil-based lubricants at the plant burn off over the next few days. Firefighters have stopped using water on the fire to prevent runoff into local waterways to avoid an "environmental nightmare," he added.

Later on Monday Illinois Gov. J.B. Pritzker announced that "out of an abundance of caution" the evacuation radius around the plant had been increased from one mile to two.

In a statement, he said that local authorities would be assisted by state emergency response personnel, including from the National Guard, Emergency Management Agency, Environmental Protection Agency and American Red Cross.

Locals were also urged to wear masks to prevent the inhalation of soot and other particulate matter.

Residents in the area have reported spot fires caused by falling debris from the burning plant. Special fire crews have been dispatched to deal with such incidents.