A tank containing a hazardous chemical solution ruptured at a paper and packaging mill in Washington state on Tuesday, killing an undisclosed number of people and leaving multiple others critically injured, according to local authorities and company officials.

The incident occurred at the Nippon Dynawave Packaging facility in Longview, Washington, where emergency crews responded to what officials described as a hazardous materials event involving a tank filled with “white liquor,” a chemical mixture used in pulp and paper production.

In a joint statement, Nippon Dynawave Packaging and local authorities confirmed that the rupture resulted in “multiple critical injuries” and fatalities. Officials did not provide a death toll and said some individuals remained unaccounted for as recovery operations continued.

A spokesperson for PeaceHealth St. John Medical Center told CBS News that the hospital received nine patients from the incident, including one person who was deceased upon arrival. Emergency crews transported victims to hospitals in Longview and nearby Vancouver after conducting decontamination procedures at the scene.

Massive emergency response

The Longview Fire Department said the incident was reported at 7:19 a.m. local time and involved a tank containing white liquor, an alkaline chemical solution commonly used to break down wood chips during the paper-making process.

According to fire officials, the damaged storage tank had a capacity of 80,000 gallons and was approximately 60 percent full when it ruptured. White liquor typically contains sodium hydroxide and sodium sulfide, chemicals widely used in kraft pulp manufacturing.

Mike Gorsuch, battalion chief with the Longview Fire Department, described the situation as a “mass casualty scene.”

About 40 firefighters and paramedics responded alongside a regional hazardous materials team. Officials said patients suffered severe injuries, including chemical burns, while emergency crews worked to secure the area and assess potential environmental risks.

Authorities emphasized that there was “no immediate threat to the public” and advised residents to avoid the area while recovery efforts remained underway.

Recovery efforts continue

The officials said that the scene remains in the recovery phase as emergency responders continue operations.”

“No identifying information regarding injured or deceased individuals will be released at this time pending notification of family members,” the statement added.

Washington Governor Bob Ferguson said state officials were closely monitoring developments and had deployed personnel from the Department of Ecology to support response efforts.

“My team and I are tracking developments in Longview closely after a major chemical explosion. Responders from our state Department of Ecology have been deployed to the scene,” Ferguson wrote on X.

The governor added: “I’m deeply saddened to hear that there have been fatalities. My thoughts are with the workers and their families, and with the first responders.”

Nippon Dynawave Packaging operates a kraft pulp and paper mill and liquid packaging facility in Longview. According to the Washington State Department of Ecology, the site employs roughly 1,000 workers and produces materials used in tissue products, printing paper, cartons, cups, and plates.