A fire broke out on Saturday at a Quaker Oats plant in Iowa following a suspected explosion, though no injuries were reported, according to fire officials.

The plant is the world’s largest milling facility.

Emergency crews from the Cedar Rapids Fire Department arrived at the scene around 4:45 p.m.

Social media footage and images captured dark smoke rising above the downtown area of the city, which has a population of approximately 140,000.

In a statement on Facebook, the department noted that an explosion appeared to trigger the blaze.

All staff members were safely evacuated and accounted for without harm, Mayor Tiffany O’Donnell confirmed in a video posted to Facebook.

O’Donnell explained that the fire occurred in a section of the plant used for product handling.

“It’s not heavily populated with employees and team members. Which, of course, in this case was a blessing,” O’Donnell said.

The origin of the fire remains unclear.

PepsiCo Foods US stated that emergency personnel responded to the incident and that an investigation into the cause is underway.

Owned by PepsiCo, the Quaker Oats brand traces its origins to the Quaker Mill Company and will mark its 150th anniversary in 2027.

The Cedar Rapids plant processes more than 2 million pounds (900,000 kilograms) of oats each day, making it the largest milling facility in the world according to the company’s website.