Multiple people were injured Tuesday morning after a major chemical tank implosion at the Nippon Dynawave Packaging Company plant in Longview, Washington, sending emergency crews to the Southwest Washington paper mill and prompting a hazmat response. Firefighters told people to stay away from the site on Industrial Way while regional hazardous materials teams worked at the plant.

The Longview Fire Department said there were no threats to the city or surrounding areas, but the scene remained active as responders dealt with the aftermath of the implosion. Fire Chief Mike Gorsuch said the response could last all day, underscoring how complex the cleanup was likely to be.

Multiple injured people were taken by ambulance to PeaceHealth St. John Medical Center in Longview and PeaceHealth Southwest Medical Center in Vancouver. Officials said several of the victims suffered chemical burns and other injuries. The company has about 550 workers at the mill, which manufactures liquid packaging board.

The plant sits in a large industrial area in Longview and is one of the region’s major paper operations. According to the Washington State Department of Ecology, the mill produces about 280,000 tons of bleached liquid packaging paperboard and wetlap and slush pulp each year. That scale helps explain why a tank failure there drew a heavy emergency response so quickly.

The implosion also revived concern around a site with a recent emergency history. A March 2024 file photo showed crews responding to a chemical explosion at the same Nippon Dynawave Packaging Company plant. Tuesday’s incident is still developing, and officials said updates are expected as the investigation and cleanup continue.