Rescue workers in Omaha searched for survivors on Monday with fading hopes after an explosion and fire at an agricultural plant.

At least two people died in the accident, the Douglas County attorney, Don Kleine, said.

The city’s interim fire chief, Bernard J. Kanger Jr., said at a news conference that at least 10 workers had been taken to area hospitals, four in critical condition and six with non-life-threatening injuries; seven others refused medical treatment. One firefighter was also taken to a hospital,