At least eight people in central Illinois were injured Sunday in an explosion at a processing plant, officials said.

The explosion happened at a Archer Daniels Midland Company plant in Decatur, Illinois, just after 7 p.m. CT, a spokesperson for the company said. It's unclear what led to the blast.

It's unclear what the extent of the injuries are for those who were hurt, Deputy Fire Chief Dan Kline told CNN in a phone call Sunday night.

The blast happened at the east plant within the company's processing complex, the ADM spokesperson said.

"ADM immediately contacted the Decatur Fire Department, which remains on the scene. Several employees were injured and transported to the local hospital for treatment," the spokesperson said. "Our thoughts are with our colleagues. We do not have a confirmed cause at this time."

The location in Decatur, which is about 40 miles east of Springfield, is the company's North American headquarters, according to its website. More than 4,000 employees work at the location.

"ADM has been a member of the Decatur, Illinois, community since 1939, when we began construction on what was then the world's largest solvent extraction plant," the company's website says. "Today, Decatur is home to ADM's North American Headquarters and is the single largest location and employee base across ADM's global footprint. More than 4,000 colleagues work here in Decatur every day to unlock the power of nature to enrich the quality of life for billions around the world."